I have a VB6 app that utilizes a non-activeX DLL (non-registering).
It’s declared via the classic Public Declare Function "Function Name" Lib "Library.DLL" syntax.
On my dev machine (XP) it works fine but when I deploy to Vista or Win7 I’m constantly greeted with a Run Time Error 48 – File Not Found for the DLL in question.
I have tried copying that DLL to every directory I can think of including every environment path on the test machine and the app path too.
These are all 32-bit test environments so it’s not a SysWow64 issue.
Possibly throwing a wrench into the mix is the fact that the application in question is an Outlook COM Addin.
I managed to install VB6 on Win7 and was able to run a tiny sample app that utilizes this DLL (outside of the Outlook process) so I know it works PROVIDED the DLL is located in App path. If I call App.Path from my DLL when I run it on the test environment it shows, to no surprise, my installation directory however the DLL is there.
I tried turning off UAC. I tried making the App.Path directory permissions open to everyone, still no dice.
You may want to check the DLL’s own dependancies. You will get the same error if it couldn’t load the DLL in question or some DLL 20 levels deep in the dependancy chain.