Running into a weird issue that's *probably* correctable but so far I haven't figured it out.
Normally, installing a new version of AMS migrates folders from the old to the new install, in our case though we're talking like 300gb of files at this point, which i didn't have time to deal with yet. So Essentially I set up AMS 6.0 on the same VM, let it migrate all the config files but not the accounts folder. I disabled the old AMS 5 install manually (but left it existing), and removed all its files to another folder, leaving the accounts folder alone, copied all the AMS 6 files to the AMS 5 directory structure, and just renamed the base folder from 5 to 6. At that point, things were running ok and as expected.
I later removed / uninstalled all the AMS 5 stuff when a few weeks had passed, and today I tried installing the 6.0.2 update. It seemed to go ok, and AMS started fine, configs / etc looked ok but Outlook now seemed to ask for passwords for all users (as if password was wrong). in admin window, all groups / users were present but trying to edit most of them resulted in 'Error: User not found' or 'Error: group not found'. I could create new users / groups ok, so I tried to rename user folders in accounts, delete the old user and recreate it, then remove the created folder and rename the original back, no dice.
My thought was there must have either been some latent registry entry that was referring to the old AMS 5 folder path (which no longer exists), that was messing up the relative paths AMS uses in its configs, or there was some config file / value i'm missing that's still referring it to that and causing AMS to not recognize the existing folder / config path correctly. I thought there might have been some discrepancy between the config file structure possibly between 6 and 6.0.2 also, but i couldn't find anything obvious - it could be there was some value setting in groups / users 6.0.2 doesn't like? The odd thing is most of my groups came up as 'group not found' but a couple of them WERE editable (minor ones that only had a few accounts for some specific purpose). BUT i didn't see what made those groups different as far as config files...
Am in the process of restoring my VM atm, but would like to work on this - 6.0.2 has some features I'd like to use but clearly I need to fix whatever this pathing issue is first...