Visual Studio 2010 not starting - Missing ATL100.DLL

Question

I tried to start Visual Studio and it said: "This application has failed to start because ATL100.DLL was not found. Re-installing the application may fix this problem".
I don't want to reinstall it (time consuming).
I also just uninstalled all the C++ stuff (I don't do any C++ work, so I got rid of it).

So does anyone know?

Solution 1

If the ATL100.DLL is missing you're likely just seeing the first missing file of a now corrupted installation. If you don't want to do a full reinstall you can attempt to repair the installation from your install source but there's no easy fix for this.

http://msdn.microsoft.com/en-us/library/e2h7fzkw.aspx#repair

Solution 2

You need to have the MS VC++ 2010 redistributable pack installed on the client machine.

You should also link your program against the release version of the redist pack and not distribute a debug version of the VC++ runtime (msvcr100d.dll) as its release counterpart is part of the VS2010 redistributable pack, as described here. The ATL100.dll is also part of that pack. MS has strict policies about which dll can be distributed with the application. A previous post about DWMAPI.DLL will help to sort out that problem.

source:iodocs.com