I could not perform Step 2 as the application hangs when attempting to open the company file (this is the primary issue)
I did perform steps 1, 3 and 4.
After creating a new user (with admin rights), I was able to open the company file the first time, and then back to hanging up when I repeat. (back to square one)
Are you sure its OK to call tech support - I read on this forum that Big Sur was not supported?
