I've got Fabric Manager 4.2 server running on a Windows 2003 box and I've been successful in the past connecting as a client]
I've gotten this before and usually a reboot fixes it. I have tried stopping the server service and starting it again, but it fails. Reboot is the only thing that fixes it.I don't know why it hangs up though.
I also had this problem. Apparently there is a bug in the back-end DB. The simplest solution (for me) was to upgrade to 4.4. Touch-wood, I haven't hit this problem since.
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