问题
Moving a working C# project from a 64-bit Windows 7 machine to a 32-bit XP machine caused the following error:
Retrieving the COM class factory for component with CLSID {681EF637-F129-4AE9-94BB-618937E3F6B6} failed due to the following error: 80040154.
681EF637-F129-4AE9-94BB-618937E3F6B6 is not in the registry so it is not properly installed, but this is same ID that was previously a problem on the 64-bit Windows 7 machine.
The solution to this error on the 64-bit Windows 7 machine was found here (change Platform Target to x86) but this does not solve the problem on the 32-bit XP machine.
How do I find the DLL associated with 681EF637-F129-4AE9-94BB-618937E3F6B6, or, even better, how do I repair this exception?
回答1:
To find the DLL, go to your 64-bit machine and open the registry. Find the key called HKEY_CLASSES_ROOT\CLSID\{681EF637-F129-4AE9-94BB-618937E3F6B6}\InprocServer32. This key will have the filename of the DLL as its default value.
If you solved the problem on your 64-bit machine by recompiling your project for x86, then you'll need to look in the 32-bit portion of the registry instead of in the normal place. This is HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Classes\CLSID\{681EF637-F129-4AE9-94BB-618937E3F6B6}\InprocServer32.
If the DLL is built for 32 bits then you can use it directly on your 32-bit machine. If it's built for 64 bits then you'll have to contact the vendor and get a 32-bit version from them.
When you have the DLL, register it by running c:\windows\system32\regsvr32.exe.
回答2:
I had the same issue in a Windows Service. All keys where in the right place in the registry. The build of the service was done for x86 and I still got the exception. I found out about CorFlags.exe
Run this on your service.exe without flags to verify if you run under 32 bit. If not run it with the flag /32BIT+ /Force
(Force only for signed assemblies)
If you have UAC turned you can get the following error: corflags : error CF001 : Could not open file for writing Give the user full control on the assemblies.
回答3:
WORKAROUND:
The possible workaround is modify your project's platform from 'Any CPU' to 'X86' (in Project's Properties, Build/Platform's Target)
ROOTCAUSE
The VSS Interop is a managed assembly using 32-bit Framework and the dll contains a 32-bit COM object. If you run this COM dll in 64 bit environment, you will get the error message.
回答4:
Move excel variables which are global declare in your form to local like in my form I have:
Dim xls As New MyExcel.Interop.Application
Dim xlb As MyExcel.Interop.Workbook
above two lines were declare global in my form so i moved these two lines to local function and now tool is working fine.
来源：https://stackoverflow.com/questions/7197506/how-to-repair-comexception-error-80040154