Susan:

I have seen this type of problem before.

What no one has asked your for is the operating system for your server and workstations. More than likely you have a mix of workstation o/s, with some still XP. Likely you also have some old XP on the network but not being used for Adagio. Even if I'm wrong I'll bet if you check all of your workstations (Adagio and non-Adagio w/s) you will find that Opportunistic Locking is not consistently set the same way as it is on your server. All it takes is one to be different, even more so is this a problem if there are still XP w/s on the network.