Retrieving the COM class factory for component with CLSID {XXXX} failed due to the following error 800700c1

Vote count:

0

This question is similar to the one already posted: Retrieving the COM class factory for component with CLSID {XXXX} failed due to the following error: 80040154 but has some important differences (noted below).

I have a .NET 4.0 (VS 2010) .exe written in C# that loads a 32 bit COM .dll written in C++.

There is an error when creating the COM .dll: Failed to create xxxx.dll. Retrieving the COM class factory for component with CLSID {xxx-xx-xxxxx-xxx} failed due to the following error: 800700c1 is not a valid Win32 application. (Exception from HRESULT: 0x800700C1).

The things that make this problem unique:

• The platform target in the Build tab for the .NET .exe is X86 (as prescribed in the link, above)


• This is a WELL SEASONED app that has been out in the field for years and the problem has never been seen before


• The problem appeared virtually overnight on a machine where it had been working properly the day before.

I'm beginning to suspect that a MSFT OS update broke the app, but want to see if anyone else has experienced something similar and has a way to fix it.

Thanks!

asked 28 secs ago

edtheprogrammerguy

3,063