If you get stuck in an endless login loop…
This is a known issue caused by a bug in the lease system.
Please download the lease repair kit VcRepairTool_FLDT_0607_3112.zip from Design Tool folder at https://webapp4.flexlink.com/myflexlink/downloadarea.htm
Sign in as guest if you don’t have any MyFlexLink account.
Unzip and follow the instructions in notes.txt.
Important: Admin rights on the computer is necessary. It's not enough to only login with admin rights, it's also necessary to follow the instructions, right click on the .bat file and select Run as admin. 

Note: We don't have admin rights for you, please contact your local IT support.

If the above solution does not solve the problem... Follow the instructions at https://software.support.flexlink.io/support/solutions/articles/35000144235-collect-and-send-log-files and send the zip file to us.