Let's say, I'm completely desperate, trying to debug this issue for the last day and a half, with a important deadline approaching...
I'm developing a project in C# targeted to 4.0 on Windows 7 64-bit and Visual Studio 2012 (thus, 4.5 .NET Framework installed) and as of yesterday afternoon, VSHOST is crashing with error 0xc000007b (The application was unable to start correctly... message) each time I open the solution (or enable Debuging host if was disabled on load). This is happening only for applications targeted to 4.0 (but it is also happening to the 4.0 solution changed to 4.5, so it does not help changing to another framework version, nor can I, as client does not (and can not) have 4.5 on workstations).
As for the app, it is WinForms and I was using VS2012 for some time now, from mid-december and it all went just fine, until yesterday. As for the computer, I've reinstalled Win7 (Pro, SP1) to vanilla, then it worked for some time and now it is crashing again. I've run Memory Tests and computer passed it...
When I create vanilla project (winforms) targeted for 4.5, it all goes well and VSHOST is loaded. But changing it to 4.0, even vanilla starts crashing...
If you've stumbled upon the same issue or even better, found a solution, please, try to help.
I've found the answer. RogueAmoeba Airfoil Instant On is the culprit.
RogueAmoeba Airfoil has "Instant On" feature, which allows to hook itself to Audio of an application. And this feature caused, that some .NET applications (as Airfoil being managed by itself) were not able to start. For the reason unknown to me, but still, I've tried to enable and disable Instant On multiple times and it yielded the expected result.