Hi, I've transfered to a new (windows 10) computer. I try to work with two different profiles, for two different accounts, as worked well on my previous computer (also windows 10). For some reason, the -no -remote isn't working at all (as in: Thunderbird won't start at all if I use this command line parameter). The -P flag works fine ,so I can start both profiles separately, just not at the same time. I've tried to start it from a command prompt to see if there was any error message, but there wasn't, it just doesn't run. To clarify: this is the command that doesn't work: "C:\Program Files (x86)\Mozilla Thunderbird\thunderbird.exe" -no -remote -P "YPT" If I take the "-no -remote" out, it works fine as long as no other session is running. Help appreciated! Justus