How to fix error code 25015 with access denied message during .NET Framework 2.0 setup

Recently, I saw a post on the MSDN .NET Framework Setup Forum indicating that a customer was having trouble getting the .NET Framework 3.0 to install on his system.

How to diagnose this error

The error log for the .NET Framework 3.0 setup (%temp%\dd_dotnetfx3error.txt) showed the following information:

[11/10/06,11:30:12] Microsoft .NET Framework 2.0: [2] Error: Installation failed for component Microsoft .NET Framework 2.0. MSI returned error code 1603
[11/10/06,11:30:36] WapUI: [2] DepCheck indicates Microsoft .NET Framework 2.0 is not installed.
[11/10/06,11:30:37] WapUI: [2] DepCheck indicates Microsoft .NET Framework 3.0 was not attempted to be installed.

Based on this information, I determined that the .NET Framework 2.0 setup was failing.  Then, I used the list of .NET Framework 3.0 setup log files to request additional information from the customer - specifically, the log file named %temp%\dd_netfx_retMSI*.txt.

When the customer sent me this log file, I found the following error that was causing the .NET Framework 2.0 setup to fail:

Error 25015.Failed to install assembly 'C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Microsoft.VisualBasic.Vsa.dll' because of system error: The process cannot access the file because it is being used by another process.

In addition, the customer sent me a log file created by Filemon that indicated that setup failed when attempting to open this file with an access denied error.

How to workaround this error

Based on the above information, I made an educated guess that there was something wrong with the folder and file permissions on the customer's system.  Fortunately, he was able to use the following steps to resolve this issue and successfully install the .NET Framework 3.0:

  1. Use the SubInAcl tool described at to make sure that the Administrators group and the SYSTEM account both have permissions to folders under %windir% and registry hives under HKLM
  2. Run the cleanup tool described at to make sure any remnants of the .NET Framework 2.0 have been removed from the system
  3. Try again to install the .NET Framework 2.0 (or in this case, try again to install the .NET Framework 3.0, which will try to install the .NET Framework 2.0 behind the scenes)

Important caveats about error code 25015

Please note - error code 25015 during .NET Framework 2.0 setup is a catch-all for many types of errors.  Therefore, the solution described in this post will likely only work if you see error code 25015 and the system error message states that the file is being used by another process and/or access is denied.  Not all instances of the 25015 error code will be resolvable with these steps.

In coding terms, error code 25015 is the else block at the end of a big if statement.  As a result, it ends up being the error code displayed after .NET Framework 2.0 setup verifies that the error is not caused by any other known fusion return code (which are defined in the file corerror.h that ships in the .NET Framework 2.0 SDK).

The customer who encountered this problem also posted this item on his blog describing this troubleshooting experience in case you are interested in reading that as well.  Hopefully this will be useful if you run into this type of error while installing the .NET Framework 2.0 on your system.

Comments (11)

  1. Robbie_Mark says:

    I have had absolutely no luck with all the fixes to this problem.

    I have a new HP Compaq nc8430 win xp S2.

    I have now worked on this problem constantly for many many hours and days!!!

    Please Help!

  2. Hi Robbie_Mark – I’m not sure what steps you’ve tried already, so please forgive me if I’m suggesting things that you’ve already tried.  Here are some possibly useful blog posts for this type of error:

    If these do not help, your best bet is probably to contact Microsoft technical support for more detailed troubleshooting assistance.  You should be entitled to a free support case for setup-related issues such as this, and you can find contact information at

  3. fred68 says:

    Windows XP Pro. Tecra M5 Centrino duo

    I used msconfig.

    I stop all services that are possible, of remaining exe s running used procexp to see if anything is accessing that dll – nothing.

    I have tried running dotnetfx in Safe mode and Safe mode with networking, I have used the cleaning tool mentioned here.

    still it says Always Microsoft.VisualBasic.Vsa.dll: Access denied.

    Obviously some evil skulldugery is occuring to get .net2.0 installed – well it ain’t working.

    This system already has vs.2003 installed,ie .net1.1, I shouldn’t have to uninstall that should I? (reinstalled that, numerous times as well over past)

  4. Hi Fred68 – I’m sorry for the hassle that this issue is causing for you.  You do not need to uninstall VS 2003 or the .NET Framework 1.1 – those products are designed to run side-by-side with the .NET Framework 2.0.

    You don’t mention trying this in your comments, so if you haven’t already, can you please try the SubInAcl tool to repair the file and registry permissions on your system to see if that helps in this scenario?  You can find instructions for doing this at

    If that also does not work, then your best bet is to contact Microsoft Technical Support for more detailed troubleshooting assistance.  You are entitled to a free support case for setup-related issues such as this, and you can find contact information at

    Hopefully this helps.

  5. fred68 says:


    "VS 2003 or the .NET Framework 1.1 – those products are designed to run side-by-side with the .NET Framework 2.0." yes thats what I thought,but was starting to doubt…lol.

    Anyway I was attempting to use subinacl, but ur blog

    is what did it, so net 2.0 is installed now.


  6. ELLIOTT says:

    Directed to this thread by Turbo Tax customer service because I couldn’t install TT 2007 despite a number of attempted fixes.  This worked easily. THANK U.

  7. DaveM1 says:

    18 months on, here’s my effort to keep this issue alive… 😉

    I’m on XP Home service pack 3 and can’t install a .NET Framework version above 1.1, which installs normally.

    I’ve tried both 2.0 and 3.5, both via Windows Update and manual download, and always get errors. I’ve tried the solutions on this page: the SubinAcl + cleanup tool, as well as disabling services with msconfig, keeping my antivirus disabled all the while. I’ve also tried unregistering and reregistering the Windows Installer as per advice elsewhere.

    The error message I keep getting trying to install 2.0 is similar to the one above, except the system error cited at the end is different: "Error 25015.Failed to install assembly ‘C:WINDOWSMicrosoft.NETFrameworkv2.0.50727Microsoft.VisualBasic.Vsa.dll’ because of system error: 0x80131018." Googling that error number just turns up a load of highly technical pages quite beyond my intermediate comprehension level.

    Finally I can’t see how to raise this with MS Support without paying for it — I’m just an end user who needs .NET to run some software. So here I am with this post. Any ideas very welcome. Thanks

  8. Hi DaveM1 – The error you are seeing is a CLR error, and it means that "The module was expected to contain an assembly manifest."  All assembly modules in the .NET Framework 2.0 setup package have correct assembly manifests, so this likely means that something on your system is preventing the CLR from parsing this manifest file for some reason.  I’m not sure what would cause that type of error though.  It might help to try to repair the files that are a part of your OS by running sfc /scannow.  It might also help to run chkdsk /R to see if there is any hard drive corruption on your system.

    If neither of those help, then I’m not sure what else to suggest.  It would be best to contact MS technical support for more detailed troubleshooting.  My understanding is that setup support cases are supposed to be free, but I’m not positive how to initiate that type of support case.  If you can’t find out how to do that via, then please contact me directly by using and I’ll see if I can help you get a support case created.

  9. shenlong says:

    Hi DaveM1,

    Maybe some antivirus is blocking the manifest from working. showed that Panda Anti virus is preventing manifests from loading. You may want to try and disable the Antivirus before runnning setup. Also, with regards to installation "Access is denied", try renaming the C:windowsAssembly folder to Assembly_ and see whether it fixes the problem. (Reference: )

    Hope it fixes the problem~!!!


  10. DaveM1 says:

    Hi Tony,

    Eureka! Just when I thought I had discovered my first-ever software problem that couldn’t be solved through a little web research, a combination of antivirus disabling and renaming the assembly folder as suggested has finally allowed .NET 3.5 to install. I suspect it was the latter that did the trick as I had tried disabling the antivirus before with no luck.

    Thanks loads, and thanks again Aaron for taking the trouble.

    Dave M

  11. SimonH says:

    Eureka II, it seems!

    After de-installing AVG, and after running various tools as mentioned, subinacl etc – drew a complete blank – then finally renamed the Assembly folder, launched .NET 2.0 install for the nth time and off it went – no bombout!. Hopefully can now install 3.0 and 3.5 .NET and I may get this laptop back to normal.


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