I’ve got PC’s running windows Vista and we don’t have a problem mapping drives.
I’m currently on V5R4 but we had V5R1 servers doing this after Vista came out with no problems.
The key is to keep things easy for the users. Keep their windows and AS400 passwords in sync and this will work without any authentication failures.
Our AS400 is using the simple password settings so case sensitivity isn’t recognized.
If your AS400 is allowing longer passwords and is case sensitive as long as they passwords are in sync you should be fine.
How to set up a mapped drive on AS/400.
Did you get around to testing this out?