Windows 7 - Issue sharing files between Windows 7 and XP

I have a small network of six computers. Five of them run XP and I just added a Windows 7 machine. I've got a Microsoft Access 2003 database that all of the computers share that is hosted on one of the XP machines. The Windows 7 machine can access the Access database through the network just fine, as long as no one else is accessing it. However, if someone else on an XP machine on the network is using the file, it won't open on the Windows 7 machine. Doubling clicking the file on Windows 7 gives me the circling blue icon for a second or two, then nothing happens. If the XP user exits the database, then I can open it fine.


Permissions on the XP that is hosting the database is set to allow everyone. And all the XP machines can access it at the same time.


Any ideas what is happening?