Can’t open file since update

Hi

Assuming you're on Windows 10, right click on the PSD and select Open with and then select Choose another app

Select Photoshop 2021 and put a check mark in Always use this app to open PSD files

If Photoshop is not listed there, scroll down and select Look for another app on this PC

Navigate to this location and select Photoshop.exe

C:\Program Files\Adobe\Adobe Photoshop 2021