Troubleshooting steps I use for Media Center component registration failure errors

I heard from a customer this week who indicated they were seeing all of the following errors that I have described in previous blog posts:

  • A Component Registration Failure error appears while trying to navigate to My TV.  The text of the error message states "Some of the files needed to play radio or video are missing or corrupt. Media Center component registration may have failed."
  • A Critical Process Failure error appears while trying to configure an internet connection during first run.  The text of the error message states "A critical Media Center process has unexpectedly failed. If problems persist, please restart your machine and try again, or contact technical support. Code: 3"
  • A Tuner Not Found error appears while trying to setup a TV signal during first run

    I wanted to outline the exact steps I took to investigate this user's computer because they are very often useful in resolving this type of error.  Hopefully, if other folks run into this type of error within Media Center, they will be able to find this blog post and be able to more easily fix the error themselves.

    The errors listed above are normally caused by a Media Center service not being correctly registered on the system.  Service registration happens at the end of Media Center update rollup or hotfix setup, and most cases I have seen of this error can be traced back to something failing during the installation of the most recent Media Center hotfix.

    The most useful log file for Media Center hotfixes is named %windir%\medctroc.log.  In this type of scenario, I always start my investigation by opening up that log file, scrolling to the bottom and looking for any errors or warnings, especially errors related to service installation.

    In general, the sessions in that log file come in pairs - an un-registration mode that is denoted by the log string Will run in unregister mode and a registration mode that is denoted by the log string Will run in registration mode.  The service un-registration and re-registration command lines appear under the heading Registering services and COM objects... in the log file.

    In most cases one or more of the following warnings or errors will appear:

    • Warning: Process wait timed out
    • Error: couldn't stop the ehSched service: 0x00000424.  -->    "The specified service does not exist as an installed service.

    In cases where I see any of the above error messages in %windir%\medctroc.log, I use the following set of steps in the order listed below to manually un-register and re-register Media Center services:

    1. Close Media Center
    2. Click on the Start menu, choose run and type cmd
    3. Execute the command regsvr32.exe atl.dll
    4. Execute the command C:\WINDOWS\eHome\ehSched /unregServer
    5. Execute the command C:\WINDOWS\eHome\ehSched /service
    6. Execute the command C:\WINDOWS\eHome\ehRecvr /unregServer
    7. Execute the command C:\WINDOWS\eHome\ehRecvr /service
    8. Execute the command C:\WINDOWS\eHome\ehRec.exe /unregServer
    9. Execute the command C:\WINDOWS\eHome\ehRec.exe /regserver
    10. Execute the command C:\WINDOWS\eHome\ehmsas.exe /unregServer
    11. Execute the command C:\WINDOWS\eHome\ehmsas.exe /regserver
    12. Restart Media Center

    The command lines above are case-sensitive, so make sure to capitalize the S in unregServer exactly as listed above.  Also, it is not sufficient to simply re-register the services because these services have logic in the code that treats the /service switch as a toggle (meaning that if it is un-registered, it will re-register it, but if it is already registered, it will un-register it).

  • In a few cases, running the above steps will result in the same error messages when launching Media Center and will show the same log messages in %windir%\medctroc.log.  I have seen the following steps help resolve these errors in this scenario if the above commands did not help:

    1. Go to Add/Remove Programs

    2. Check the box labeled Show updates at the top

    3. Scroll to the bottom of the list of installed programs

    4. Remove the most recently installed Media Center update rollup package

    5. Re-download and re-install the update rollup package that you uninstalled in the previous step

    <update date="2/19/2006"> Added additional steps to uninstall and reinstall the most recent Media Center update rollup because I have heard from a couple of customers who tried all of the above command lines and none of them helped, but uninstalling and reinstalling did end up solving the issue for them </update>


    Comments (54)
    1. Clochard69 says:

      I’ve been up all night and morning trying to fix these annoying problems but it just won’t work. The mayor problem seems to be that the ehRecvr.exe won’t start (or at least doesn’t stay on) If I try to watch live tv or even setting up the tv-signal it (ehRecvr) crashes and takes it all down. then a pop-up keeps showing ehRecvr had to shut down…asking me to report the problem…

      drivers are up to date

      I really don’t know what to do 🙁

    2. chrislehr says:

      This is why once I had MCE working the way I liked, I ghosted the C drive.

      I also made my C drive only 20gb and my M drive is the other 380gb.  I can quickly ghost and "start fresh"

    3. Stewart Tansley says:

      Thanks for your efforts Aaron, but I am still seeing a beep and then "Component Registration Failure" on switching to Live TV on MC startup. MC is also reporting that I have no saved recordings (! — I have a lot).

      If I hit My TV rather than Live TV at MC startup, I get Component Registration Failure and then immmediately also the Critical Process Failure message, then another Component Registration Failure msg. I’ve not seen the Tuner error that you mention. Going to the Guide also gives Critical Process Failure. Despite these messages, I am able to see Live TV, but I can’t get to my recordings from within MC.

      I’m seeing this problem since I installed "Update Rollup for Windows XP Media Center Edition 2005 (KB912067)" today, 2/18. I have had previous similar problems with such Update Rollups and now fear every time one comes out. :-/

      Please let me know if you want to see my logs.

    4. Hi Clochard69 – Have you tried running ehrecvr.exe /unregServer and ehrecvr.exe /service to see if that will resolve the crash that you’re seeing?  You may also want to try installing the latest Media Center hotfix from

      Hi Stewart – I would like to see your log files if possible.  Can you please email me the logs listed at

    5. Clochard69 says:

      hey aaron tnx for your time allready,

      ehrecvr.exe /unregServer and ehrecvr.exe /service does stop the crash but the ehrecvr.exe service stops a few seconds later and I can’t get it working again.

      Not even after I install KB912067 (jan. update)

      So I tried a system restore right after the installation of rollup 2 (KB900325) then I installed all the high priority updates 1 by 1 and rebooting after each install, just to make sure (updates KB911565, KB887998, KB904706, KB910393) and for now everything seems to be working (*fingers crossed*)

      Optional updates remaining uninstalled:

      KB912067, KB829019, KB909520, KB909993, KB900930, KB896344, KB887797

      Now the strange part is that when I turn on automatic updating, KB908250 starts asking to be installed…

      What would you suggest, installing KB908250 or

      leaving everything like I’ve done so far or installing some of the remaining updates (if so in which order excactly pls)

      thank you

    6. Hi Clochard69 – The only updates that you have not installed yet that are specifically for Media Center (as opposed to general Windows XP hotfixes) are KB908250 and KB912067.  KB908250 is superceded by KB912067 (meaning that all fixes in 908250 are also in 912067, but 912067 also has some more fixes).  I would suggest trying to re-install KB912067.  If you start seeing crashes again, you can revert back to the most recent system restore point, and if you do see issues can you please send me the file %windir%medctroc.log so I can try to take a look and see if I can figure anything out?  You can contact me via

    7. msghockey says:

      Aaron, I am still having my problem with AIM conflicting with WMC 2005 I get the tv tuner is not avalible mesg. I seen my log and ctrl-f’ed my errors and here is what i got:

      "SetupInstallServicesFromInfSection [freestyle] successful. (Error status: 0x00000000)."  and

      "Error: couldn’t stop the ehRecvr service: 0x00000426."

      I tried all of your steps and still cant get this to work. PLEASE HELP ME

      MY SN on AIM is : MSGHOCKEY

      My email:

      If somebody could contact me personally I would be very grateful


    8. Clochard69 says:

      Hi again. I’m glad to report that everything is working perfect over here.

      Sadly it was a stupid mistake from me. I had installed a codec pack that worked before the rollup, but after it would result in a crash.

      Anyway tnx for all your time and effort.

      Keep up the good job!

    9. Hi Msghockey – The error message 0x00000426 means "the service cannot be stopped because it has not been started", which is usually OK to ignore.  I will email you and follow up and try to look but I’m afraid I won’t be too much help because I am not sure I know enough about AIM.

    10. Fendando says:

      This helped me.  You should really make a batch file of this.

    11. Peter says:

      Hi there.  Must say I appreciate all your suggestions, time & effort to help all us out.  I’ve got MCE 2002 Service Pack 2 installed, and something nearly identical happened before: Upon starting MCE, the error msg appeared "some of the files needed to play radio or video are missing or corrupt."  I can’t see any TV, recorded or live, but I can start Sonic & view the recorded shows, so it doesn’t seem to be a hardware problem.  Radio says no tuner could be found.  Although I didn’t see the above error msgs in MedCtrOC, I did the above commands (changed to WINNT in MCE 2002), but to no avail.  Uninstalling & reinstalling the TV tuner (AVerMedia AVer TV Tuner) didn’t do anything, either.  Uninstalling & reinstalling the updates after the last successful TV watching/recording didn’t help.  The last time this happened, I used system restore to go back a week or two.  Now, system restore won’t even work.  The only thing I can give you are the warning messages in MedCtrOC, which are slightly different than what you mentioned, & could shed some light on the issue.  If there is anything else I can tell you bt my system, let me know.  Thanks, Peter

    12. Hi Peter – please let me know what warnings/errors you are seeing in %windir%medctroc.log and I will try to see if there is anything I can figure out from that…

    13. Peter says:

      Thanks!  Here’s three warning messages:



      Executing line "C:WINNTehomesnchk.exe C:WINNTehomeehRecObj.dll"

      Assembly ehRecObj.dll is delay-signed

      Warning: Failed to delete regkey


      Executing line "C:WINNTehomesnchk.exe C:WINNTehomeehshell.exe"

      Ver ‘C:WINNTehomeehshell.exe’ == 5.1.2600.1217

      Process Return Value: 0x00000000  –>  The operation completed successfully.


      Assembly ehshell.exe is not delay-signed

      Warning: Failed to delete regKey SOFTWAREMicrosoftStrongNameVerificationehcommon,31bf3856ad364e35


      Registering services and COM objects…


      Executing line "C:WINNTehomeehSched.exe /unregServer"

      Warning: Process Return Value is 0x800736b7 –> The requested lookup key was not found in any active activation context.

      Error: Failed to call ehSched.exe with parameter(return value: 0x800736b7).

      There are more, but they’re mostly the same.  I can send you the whole file if you want.  Thanks for checking them out.


    14. Hi Peter – The first 2 warnings are from very old versions of Media Center.  I cannot tell which version of Media Center the 3rd warning is from, you would have to look at the beginning of the logging session that it is associated with and look at the file version reported there.

      However, I’m not sure what to suggest for your scenario beyond the command lines listed at the top of this post.  It might help for you to try running the mcerepair tool from

      I’m sorry I’m not able to be more helpful here.

    15. BigDog1 says:

      Mr. stebner can you please help me? I had a very good working and configured MCE system untill I decided to upgrade my tuner card. When I encountered problems with the upgrade my recearch led me to your site. Here I found out that the problem was with .net framework 2.0. However I am unable to remove it from my system. To get my system back in working order I need to re-install MCE, but I always get an error message close to the end of the install ater CD2 has been inserted: ".net framework initialization error. MCE components cannot be registered." If I choose OK the error seem to go away but returns when CD1 is re-inserted. Click OK again and the install neem to go fine but at the end you find that the install is no good. If I do a complete clean install this problem does not show. However I a tryinh to preserve my configuration from previous. What can I do?

    16. Hi BigDog1 – It sounds like you are re-installing Media Center but not reformatting your system.  If reformatting during the re-install is not an option, you will need to try to remove the .NET Framework 2.0 using some other means.  I think the simplest route would be to use the steps listed at to manually remove the .NET Framework 2.0, then use the steps listed at to remove and re-install the .NET Framework 1.1.  Hopefully this will clear up that .NET Framework initialization error that you are seeing.

    17. XOR42 says:

      Thnaks for the tip on component re-registration.  I was also plagued with the ehRecvr.exe application error.  I created a CMD batch file with your commands and a final PAUSE.  Although it ran VERY slowly (10 sec to to 2 minutes per pair) and it seemed to hang at the ehmsas.exe deregister, it did stop my ehRecver.exe boot error.  At least on the last boot (knock on plastic).

      As a side note, I also have a TV tuner, but unlike others, mine doesn’t have any drivers or software.  It’s the external Adaptec USB Dual Tuner box with FM tuner that is compatible with MCE’s built in tuner support.  

      My Adaptec tuner actually worked worked fine w/o the ehRecvr.exe error.  It weas only after I installed ULead’s Media Studio Pro 8.0 video editor that it started occurring.  Perhaps it is related to commonly used capture drivers that might be installed with some TV tuners or video software such as MSP8.


    18. section says:


      i have a toshiba qosmio G20 with MCE 05. the other night i decided it was time to watch some TV on it… anyway everytime i click on MY TV i get

      szAppName : ehRecvr.exe szAppVer : 5.1.2710.2732 szModName : unknown

      szModVer : offset : 51000000

      when i first boot into windows that error pops up. but if i try to use my tv in mce i pops up every 5 seconds.

      i just installed the new MCE 05 rollup and uninstalled reinstall my tuner cards drivers. i tryed you commands above and no luck..

    19. Hi Section – You might want to try the repair tool located at and see if that helps resolve this issue on your system.  Hopefully this will help.

    20. section says:

      Tried that no love… it refuses to run on my computer saying its an unsupported language.

    21. Hi Section – What language operating system do you have?  I am not sure what to suggest here if the above commands didn’t help and you cannot run that tool.  It might help to fully uninstall Update Rollup 2 and any hotfixes installed after Update Rollup 2 (such as KB908250 or KB912067).  Then you can try to re-install Update Rollup 2 and the latest hotfix (KB912067).  There might also be some information in your application event log that helps narrow down why this crash is happening.  I’m sorry I’m not able to be more helpful here.

    22. section says:

      i guess my operating system is using english(Australian)…

    23. Mike says:

      I had the basic problems with media center as stated in the previous logs. Everything is working fine now. I think the problem began after updating media center from windows update. I fixed it by uninstalling .net framework 1.1 and 2.0 and other updates for .net framework and then I reinstalled .net framework 1.1 and the updates for .net framework 1.1. I then installed the media center update. I checked the media center program and it was operating perfectly and then I installed .net framework 2.0 and what other updates that were suggessted and everything is working better than ever. I think the problem may have been installing the update with .net framework 2.0 installed beforehand. I suspect that if someone is having the same problem that they may be able to get away with just making sure .net framework 2.0 is not installed and then reinstalling the update for .net framework 1.1 and then reinstalling the media center update.

    24. Harry says:

      I had a problem with my AverTV E506 card not being found within media centre. It worked OK with AverTV application. I followed the steps Aaron gave above. The first steps (un-reg and re-reg services) did not work.

      However un-installing and re-installing RollUp 2 update did the job. Immediately media centre found the TV card and everything is OK.

      A big thanks to Aaron. Great help


    25. section says:

      so far i’ve tried everything suggested and no love:(.

      i’ve uninstalled both mce updates and .net updates and reinstalled them in varying orders and nothing has changed still at the same place… this thing just hates me.

    26. Paul Arnold says:

      Aaron,  Thanks very much indeed, worked a treat. Paul

    27. Daniel says:

      Yeah, i too have a problem with MCE 2005 recognising my WinFast DTV1000 T Tuner card…

      I have done your steps numerous times and even reformatted and installed in recommended sequences and still no luck…

      I tried using the tuner WITHOUT Rollup 2 and it worked – although it was barely usable and then i installed Rollup 2 again and says that it cant find the tuner… i have looked everywhere and tried like everything and still no luck… i downloaded MediaPortal to see if there was a problem with my Tuner and it works perfectly on there.. so it’s a problem with bloody MCE2005…

      Is there a way to like… force MCE to read a tuner or am i out luck and stuck with a lemon of an OS? Coz i have seen and heard of people using this card with no problems or at least solved theirs…

      Any suggestions would be great! Thanks guys…

    28. cm says:

      The ehrecvr.exe error message is gone and my tv tuner is working!  I just installed Microsoft’s update KB912945 and the ehrecvr.exe message disappeared.  I installed the update to correct some time of active X error in internet explorer which coincidentally started to appear the same time the enrecvr.exe error message started.  I think both were associated with the rollup 2 for MCE 2005 which I installed in March.  The script error message did disappear immediately.  I then checked "services" and it said ehrecr.exe was started so I went to media center and was able to watch tv on the PC monitor.

    29. Wayne G says:

      As for one member stating the possibility that .net framework 2.0 may be a cause to the persisting "no tuner" problems, my computer is one case that had problems even without ever having .net framework 2.0 installed.  I’ve tried different combinations as well.  Installing .net frame 2.0 last didn’t help MCE detect my tuner cards as well.

    30. d sutherland says:

      yeah! the unreg/reg sequence fixed the annoying crashes!!!

    31. JohnThomasCraig says:

      When I start Windows MCE 2005, I get an exception from ehRec.exe.  I have tried using the re-registration steps mentioned in this post as well as the MceRepair tools from Peter’s blog (16.7s).  Also tried installing .net 1.1 and the last rollup for MCE again.  I think this all started for me when I installed Visual Studio 2005 Standard.  What other steps can I try to get Media Center working again?

    32. Hi JohnThomasCraig – I don’t know of any issues in Windows Media Center that are caused by installing Visual Studio 2005.  Do you see any errors in your application event log when this exception occurs?  Also, is there any exception information in %windir%ehomeehshell.crash that might narrow this down?

    33. RareButSeriousSideEffects says:

      I’ve tried getting Rollup 2 installed without losing tuners about 5 times now, without luck. More detail on that in another thread, but a specific thing I’ve noticed is that every time I try these various post-install fixes for the component registration part, the <C:WINDOWSeHomeehmsas.exe /regserver> command never actually returns control to the command prompt or batch file it’s run from. When run from the Windows Run dialog, there’s a brief hourglass, but no obvious indication of success, failure or even execution completion.

      Is there any test for success on this particular command?

      (As an aside, I’ve seen lists of batch commands that place the medctrro command *after* the ehmsas /regserver command, and it would seem doubtful that medctrro is being executed in those instances.)

    34. Hi RareButSeriousSideEffects – I don’t know of any specific test for success, but generally the tuner not found issues that I’ve seen have been caused by registration issues with ehRecvr, ehRec and/or ehSched and not ehMsas, so it may be possible to just ignore that issue that you’re seeing.

    35. Since the Windows Vista public launch in January 2007, I have been receiving questions more frequently

    36. This article serves as a central location for all links to troubleshooting documentation that has been

    37. Bluefire says:

      Thanks so much for this guide.  I was very frustrated trying to correct this problem and almost went so far as reinstalling the entire system(a very long prceess) on my computer.

    38. rotaryfiend says:


      I am getting the same error.  I am trying to install rollup update 2 and let me tell you.  What a fiasco.

      at installation of KB895961 I get an error telling me the install was not successful…blah.

      I uninstalled the rollup (installed fine with SP3, but the extender software would not install with SP2…wound up rolling off SP3 and taking it from there).

      now I am trying ot get it back with SP2 only and no matter what services I bounce, etc…nada.

      Here is what the log tells me:

      Executing line "C:WINDOWSeHomeehRecvr /service"

      Warning: Process Return Value is 0x000005de –> The event log file is full.

      Error: Failed to call ehRecvr with parameter(return value: 0x000005de).

      grrrr…not good.

    39. Hi Rotaryfiend – If you are getting an error about the event log being full, then I’d suggest running eventvwr and right-clicking on each of the event logs and choosing to clear them, then try the Media Center registration steps again.  Hopefully this helps.

    40. mattrane says:

      Hi Aaron,

      Thank you kindly for the wealth of information you have amassed here on problems with Media Center. I’ve tried several of the suggestions, but am reluctant to try some of the ones tinkering with the registry because I don’t want to mess things up further. Some guidance would be greatly appreciated. Here’s the issue:

      I have a Gateway GM5420 running Vista Home Premium. It has a Vixs PureTV-U 4899 as a tv tuner. I also have an Xbox 360 hooked up to the computer (and as an extender). What happens is that I constantly, but not always, get the "Tuner not available" message when trying to watch live TV. I was having this problem about a month ago and decided to reformat the hard drive and reinstall Vista. Things worked smoothly for about a month, but now I once again am getting the Tuner not available error. Sometimes, if I restart the computer, the tuner will work, but sometimes not. Oh, and error in the event viewer seems nondescript:

      Log Name:      Media Center

      Source:        ehRecvr

      Date:          3/5/2009 6:58:13 PM

      Event ID:      3

      Task Category: None

      Level:         Error

      Keywords:      Classic

      User:          N/A

      Computer:      Gateway


      The description for Event ID 3 from source ehRecvr cannot be found. Either the component that raises this event is not installed on your local computer or the installation is corrupted. You can install or repair the component on the local computer.

      If the event originated on another computer, the display information had to be saved with the event.

      The following information was included with the event:

      ViXS PureTV Analog TV Tuner


      the message resource is present but the message is not found in the string/message table

    41. Hi Mattrane – I’m sorry for the hassles that this issue is causing for you.  I’m not sure why you would see this error sometimes but not others.  One thing that could cause this is if you have some other program or process running on your system that accesses your TV tuner card.  Media Center is not able to access a TV tuner if another program is already using it, and in that scenario it will give an error that the tuner cannot be found.

      If that isn’t the case on your system, then I’d suggest posting this question on one of the following forums to see if anyone there can help suggest any other workarounds for you to try:

    42. mattrane says:

      Thanks Aaron. How do I identify whether another process is accessing the tuner (I did the thing where you disable all non-MS services). Could it be the xbox?

    43. Hi Mattrane – No, the Xbox does not use the TV tuner on the Media Center PC.  The most common causes I’ve seen are Media Center add-ins or other programs that are used to remotely schedule TV recordings.  If you don’t have any programs like that installed, you can try to use one of the Sysinternals process monitor tools ( to see if you can find any processes running behind the scenes.

      If that doesn’t help, I’d suggest posting this scenario on one of the forums I listed in my last reply.

    44. Molly Do-It says:

      You are incredible!  Thanks so much for these instructions — my Media Center was working great, and then one of the infamous Microsoft updates caused it to have issues.  Your well written step by step directions saved my sanity (and probably my computer…)!  Thanks again!!

    45. Nicola says:

      Hi.  I have just carried out the above fix as my XL-100 tuner suddenly stopped working and IT WORKED.  Fabulous.  So just wanted to say thank you and say this fix is still relevant as at September 2012.  Thank you so much for posting.  

    46. Jackson says:

      would love to do this and have my problem fixed, about 12 forums couldn't figure this out.

      I keep getting Dcom error 10005

      DCOM got error "%1058" attempting to start the service ehSched with arguments "-Service"

      in order to run the server

      4B635ECB-0887-4015-8CA6-D621362F98D1 in my eventlog.

      Pleassssssssssssssssse let me know that this page will help.

    47. Hi Jackson – I don't recognize this error message, so I'm not sure if the steps in this blog post will help you in this scenario.  These steps won't do any harm though, so it is probably worth trying them if you haven't yet.

    48. KPatchery says:

      Hi Aaron – I've used your blog for several fixes on my old XP MCE box, so thanks!

      My problem: ehrec.exe takes up 100% of 1 CPU after the PC has been running for ~12 hours or so. No errors in medctroc.log or the Media Center Event Log. I reboot just to make sure things are OK. ehrec.exe again runs normally after the reboot.

      These steps above have not helped. Do you have any advice?

    49. Hi KPatchery – I'm sorry, but I don't know what else to suggest for this type of issue beyond what is already listed in this blog post.  If those steps don't help, then I'd recommend posting a question on the Windows XP Media Center forums at…/14.aspx and hopefully someone there will have some additional suggestions for you to try.

      I'm sorry that I haven't been able to be more helpful in this scenario.

    50. KPatchery says:

      No problem, Aaron. This was a long shot, as you haven't looked at the XP MCE code in many moons.

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