We have a custom built client/server application developed in VisualBasic 6. VB 6 is unsupported development/deployment environment since March 2005. Recently, I stumbled on a bug with library DBGWPROC.DLL while trying to install client part of application on Windows 7 x64 (as far as I can tell, this error is related to x64 version of Windows 7/2008R2). Here is a recipe which I used to overcome the installation error:

1. Author released the library to public domain, so get the newest release from here, more precisely from here.
2. unzip library to C:\Windows\SysWOW64
3. execute library registration at command line:

   cmd> cd C:\Windows\SysWOW64
   cmd> regsvr32 DbgWproc.dll
   

   If you’re doing registration on Windows 2008 R2 SP1 registration should succeed without the error, if you’re doing registration on Windows 7 x64 SP1, you’ll likely receive an error but you can ignore it (at least in my case everything worked as expected afterwards.Your millage can vary!)!

4. install your application that is using DBGWPROC.DLL from your msi, when you receive error regarding DBGWPROC.DLL, simply ignore it.
5. Test the application. Mine worked as if it was installed on Windows XP.