Auto Analyze SQL throws errors "Failed to create session for Toad"; "Group does not exist"

Running Toad for Oracle Xpert 12.6 with DBADMIN add-in module. Environment is virtualized remote desktop (enterprise) running Windows 7 Professional.

When I try to analyze even very simple SQL, it throws the errors mentioned in the subject, followed by a fully qualified path and filename. The path is to the effect %appdata%\Roaming\Dell\Toad for Oracle\12.6\SQL Tuning\TEMP104843023\TEMP104843023.ogd. Of course, the number following TEMP changes with each iteration. I have tested the path below SQL Tuning, and I am able to create files and directories there.

I was previously able to run Auto Optimize SQL without error. I use it rarely, so it has been a few months.

Thanks in advnance

JimR