@nyamoga9 you might just need to modify the registry fix
Try this one: excel.application.2020.txt (560 Bytes)
This has been fixed in 10.2.300, 10.2.400 apparently and if you used the old registry fix then of course you would be pointing it to a non-existing Excel hence the Gray out. I would either use the new fix or avoid using the fix all together in order not to corrupt the new settings with old values. (assuming you have it running on your GPO or something)
I have no issues because I never used the old reg fix either.
You might want to check your regedit see if you are on .16 maybe there is a .17 even which I dont see in mine.