n't use the snapshot feature because it's too slow (and frankly don't trust it). I manually copy a VM file to an external disk prior to (and after) any Parallels updates because I've been stung with messed up VMs by the install process before. I simply restored the backed up file to /Library/Parallels afterwards to bring it back to the original TPM settings. Doubtful that bitlocker is actually used on my system and the actual issue is Parallels implementation of TPM in Intel-based Parallels, given what MSInfo is reporting. Should also add that I'm doing this on an early-2013 MBP (10,1) running Catalina (10.15.7), which likely contributed to the performance issues.