Hello. I'm having the same problem too, only with the clients. The server manager license installed just fine.
I tried Bill's suggestion, Stopped 2 BESR services, deleted the one .slf file I found which I'm guessing was the manager, then started the services and opened the manager. I immediately got prompted for a license file, I did and then tried to add a Client license and it says "The license file has already been imported". Though when you look at the licensing window it is blank with any files.
Any other suggestions or info you'd need?
Thanks, Jim
PS- I migrated from LSRM 6.02, shouldn't make a difference though I would think.