I just set up a fresh development environment. Windows 10 VM with Sage 300 2019 PU5.

When I run a program from VB6 IDE and I'm logged into Sage 300 the program fails with a non descript error when trying to create/join the session.

SessMgr.CreateSession "", lSignonID, Session

If I exit out of Signon Manager and run a program from the VB6 IDE the program runs fine but I can no longer sign into Sage 300. I get the following error when trying to sign in. 

"Cannot connect to Sage 300 Signon Manager"

It's like whoever grabs the Signon Manager first holds it exclusively. I never had this issue under my Windows 7 VM. The executable runs fine. It's just an issue within the IDE. 

I've tried turning UAC off and I have uninstalled and reinstalled Sage.