change config, not recognised by Synergy

[Sverre Rakkenes 1]

my server is on linux mint. have used it with a windows 10 guest for a long time, and then I added a second guest (also windows 10). Then, I removed the second windows guest, and after that, the old windows 10 is laggy, and in my log the server says that the new windows 10 (the one that I have removed from my config) is missing.. it can not find it. If I add that 2nd windows box in config again, then it works fine, and if I remove it again, it is laggy.. so e.g I am unable to remove a PC from synergy.. I have tried to ugrade to the beta version of both server and client, but I have same problem.. seems like it actually does NOT use the config at all.. what to do?