The problem turns out to be some misplaced/invalid system files on the user's machine, which can manifest as "The Application was unable to start correctly (0xc000007b). Click OK to close the application" when starting certain applications.
The problem was due to 32/64-bit mismatches of various system dlls required by Visual studio. Somehow the dlls it needs got replaced by 64-bit versions that it couldn’t load.
Replacing the dlls mentioned below from a machine that is working solves the problem:
c:\Windows\SysWOW64\msvcp100.dll c:\Windows\SysWOW64\msvcp100d.dll c:\Windows\SysWOW64\msvcr100.dll c:\Windows\SysWOW64\msvcr100_clr0400.dll c:\Windows\SysWOW64\msvcr100d.dll
http://social.msdn.microsoft.com/Forums/en-US/vssetup/thread/96035692-9a50-40d4-a7d3-48bda87d11ec