George Karnos
Ansys Employee

Fluent and Redhawk are the only programs supported on the ARM CPU.
Please see the following post for more information.
https://forum.ansys.com/forums/topic/m1-mac-issues/

Testing is not done on parallels.

That being said, a coupe items to check:
Rename the %APPDATA%\Ansys\v2##  to v2##.old then try to run.
Also, check your PATH
Open a DOS Command prompt and type in:

set PATH
This will display your PATH.
make sure it starts with:
C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C