This happened to me also, took me a long time to work out what was causing it. For me I noticed it only occured for IE 6 users. There is a new option in it that blocks certain cookies, goto TOOLS -> Internet Options -> Privacy Tab, change the slider to the bottom to accept all cookies and hopefully that should fix your problem!
Donate to UBBDev today to help aid in Operational, Server and Script Maintenance, and Development costs.
Please also see our parent organization VNC Web Services if you're in the need of a new UBB.threads Install or Upgrade, Site/Server Migrations, or Security and Coding Services.
