When comming out of hibernation OC locks up and does not sign in. We have to cancel the current sign in and try again or close OC(exit or force the app to close using task manager) and open it again.
hi What OS do you using, I has run into the same issue when i used the OC version on the win 7 rc, but made a tested it again by using the RTM version, everything is ok now. So i suggests that you can upgrade the OC to the latest version, 3.5.6907.37. And confirm you have do check the "Automatically start Communicator when i log on to windows". Did the issue happen to one client or all the clients? Please test it in different OS client, and give us your result.