A customer recently contacted me due to a problem they were experiencing while trying to install the .NET Framework 2.0 on the x64 version of Windows Server 2003. I took a look at the verbose log file for this scenario and saw the following error:
Action start 9:16:59: CA_InstallAssembly.3643236F_FC70_11D3_A536_0090278A1BB8.
MSI (s) (B0:F8) [09:17:03:906]: Product: Microsoft .NET Framework 2.0 (x64) -- Error 1719.The Windows Installer Service could not be accessed. This can occur if you are running Windows in safe mode, or if the Windows Installer is not correctly installed. Contact your support personnel for assistance.
Usually when I see error 1719, I recommend that the user try to repair the Windows Installer service. However, in this case, that didn't seem to help, and I had to refer this customer to the Microsoft technical support team for further assistance.
Our technical support team looked at this scenario in more detail and found that there was an additional set of steps needed to repair the Windows Installer service on a 64-bit OS.
Here is a complete set of steps that should allow you to repair the Windows Installer service on a 64-bit OS:
- Click on the Start menu, choose Run, type cmd and click OK
- Run this command: %windir%\system32\msiexec.exe /unregister
- Run this command: %windir%\syswow64\msiexec.exe /unregister
- Run this command: %windir%\system32\msiexec.exe /regserver
- Run this command: %windir%\syswow64\msiexec.exe /regserver
- Restart the computer
After executing all of the above steps, you can try to re-run the failing setup and hopefully get better results.
Note that this workaround is documented in this knowledge base article, but the extra steps that are needed on 64-bit operating systems are somewhat buried in the middle of that article and can be easy to miss.