Visual Studio 2015 won't start: side-by-side configuration is incorrect

Question

When installing VS 2015, the installer was interrupted and the process was terminated. Later I successfully ran the installer again. However, the program won't start. Clicking the icon does nothing. I tried running 'devenv.exe' manually and got this message:

Program 'devenv.exe' failed to run: The application has failed to start because its side-by-side configuration is incorrect. Please see the application event log or use the command-line sxstrace.exe tool for more detailAt line:1 char:1

Using sxstrace.exe, I got the log, which is huge. Notably, this appears multiple times:

INFO: Did not find the assembly in WinSxS.

and it ends with this message:

ERROR: Cannot resolve reference coloader80.dll,processorArchitecture="X86",type="win32",version="1.0.0.0".

I have tried repairing the installation as well as uninstalling/reinstalling. I also tried a forced uninstall ([installer_file] /uninstall /force).

I'm using the web installer.

Answer 1

If anyone is struggling with similar error in VS 2019 (like I just was) there might be an easier way than uninstalling and reinstalling everything.

After I was running:

"C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\IDE\devenv.exe"

The error was:

The application has failed to start because its side-by-side configuration is incorrect. Please see the application event log or use the command-line sxstrace.exe tool for more detail.

Initially I even thought the errors might be coming from Registry settings Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\SideBySide\Winners\ as also suggested on some websites, but it wasn't the case.

I have also reinstalled both vcredist2015_2017_2019_x64.exe and vcredist2015_2017_2019_x86.exe, but this was not needed it seems.

As Visual Studio 2019 was still not starting I checked the Event Viewer logs. There under Administrative Events I have finally noticed SideBySide errors.

The errors were:

Activation context generation failed for "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\IDE\devenv.exe".Error in manifest or policy file "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\IDE\VC\VC.MANIFEST" on line 0. Invalid Xml syntax.

and

Activation context generation failed for "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\IDE\devenv.exe".Error in manifest or policy file "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\Common7\IDE\VsWizards.MANIFEST" on line 0. Invalid Xml syntax.

I tried simple renaming of the files affected: VC.MANIFEST to VC.MANIFEST_ VsWizards.MANIFEST to VsWizards.MANIFEST_ and afterwards VS 2019 started without a problem. The absence of the files doesn't seem to bother the program.

Answer 2

I have visual studio 2012 already installed. After installing Visual studio 2015 I got that side by side error. After performing following simple steps issue solved.

1. Control Panel\Programs\Programs and Features -> select visual studio 2015 from list -> change -> repair.

Note:- Keep your internet connection on. That's it for me.

Answer 3

The problem was a broken Visual C++ Redistributable 2015 installation, resulting from the interrupted setup. Visual C++ Redistributable 2015 was not shown in Programs and Features, so there was no way to uninstall it, or even know that it was installed. But VS 2015 setup was apparently assuming it was installed.

I used this tool to find and uninstall Visual C++ Redistributable 2015. I then fore-uninstalled VS 2015 and reinstalled it (possibly after a restart).

I also uninstalled all other versions of Visual C++ Redistributable that were shown by windows, but this was perhaps unnecessary. Later I repaired VS 2017, so that Visual C++ Redistributable 2017 was installed as well.

Now both VS 2017 and VS 2015 are working.