A friend told me that some on my VB6 projects were having an error when opened on Win7 machine. "Object Library Not Registered"
Looking at the .log files created for the forms, it was the mscomctl.ocx that was not loading for some reason.
After a fair amount of googling it appears that this broke back in August with the installation of IE10. Other users also made reference to ADO not working with some security updates.
After more and more googling, a fix turned up that worked for me:
cd C:\Windows\SysWOW64\
regtlib msdatsrc.tlb
In related news, I tried opening a project built on a Win7 machine the other day and had the problem that mscomctl would not load. In order to fix this on my XP system, I had to open the vbp and frm files in notepad to manually change the version for MsComCtl.ocx from 2.1#0 to 2.0#0