Groups permission problem

[subnet_rx]

I have set up many groups that each have their own permissions to a forum. Lately though, I have several people that have joined a group to get in a forum and cannot view the forum. Everyone else in the group can view the forum, just not the newest people that joined. The permissions are set so that everyone but people in the group are denied viewing or posting. I've confirmed that the people are in the group. What could be causing this?

[Jose Amaral Rego]

• Basic Concept: Membership to Multiple Groups

[subnet_rx]

Yeah, I have that part down. Like I said, these users are in the group. Other users in the group can see the forum. With vBulletin permissions, a yes overrides a no. So, it seems rather impossible that someone in the group that has permissions to view the forum cannot view the forum. Even if they were in 100 other groups that said they couldn't view that forum, it shouldn't matter.