You shouldn't be using the -no-remote command with the "default" Profile.

I start one copy in first window with -no-remote and the other three with -no-remote. However default FF seems to be running when all the others are shut down. My detail notes are below Multiple versions of Firefox As I have implemented the multiple desktop feature of Windows see http://technet.microsoft.com/en-us/sysinternals/cc817881 and this allows you to run multiple copies of Internet Explorer, but as Firefox is my preferred browser I wanted to be able to use that in any of the four virtual desktop. Initially I had two profiles for Firefox default user and Default User. I have changed the name on default user to fourth desktop and created three others first, second and third desktop. I have set up now five short cuts which are set up with the name of the profile and also in three cases –no-respond So for the first desktop I have "C:\Program Files\Mozilla Firefox\firefox.exe" -P "first user" for the second "C:\Program Files\Mozilla Firefox\firefox.exe" -P "second user" -no-remote and similar for the third and fourth The fifth shortcut is "C:\Program Files\Mozilla Firefox\firefox.exe" –P and enables me to start any profile. I can start and make enquiries on four versions of Firefox on the four desktops BUT if there is a link from a document or email an error message comes up saying Firefox is already running. Another interesting thing is that even when all copies of Firefox are shut down and I try to start the default profile it says that it is already running.

I believe that I may now have solved my problem in that I have found that I had two default users. Even though I had renamed one as fourth user it was still intrinsically called default user when you checked on the profile. I now have one default user and 4 others called first second third and fourth all with -no-remote setting in shortcut

The name of the Profile has nothing to do with which one is recognized as the default Profile, that is determined by which Profile has the Default=1 line under it in the profiles.ini file.

As far as that message "Firefox is already running", maybe you have a Profile that isn't closing properly, IOW it is "hung".
https://support.mozilla.com/en-US/kb/Firefox%20hangs
See hang-at-exit

Thanks for reply- my profiles.ini below Does this mean my 'default' is last one used?

[General] StartWithLastProfile=1

[Profile0] Name=Default User IsRelative=1 Path=Profiles/6so2b22l.Default User

[Profile1] Name=second user IsRelative=1 Path=Profiles/cuuaupu1.second user

[Profile2] Name=third user IsRelative=1 Path=Profiles/jb3h5f91.third user

[Profile3] Name=first user IsRelative=1 Path=Profiles/qpm5pm27.first user Default=1

[Profile4] Name=fourth user IsRelative=1 Path=Profiles/hkbvfnsb.fourth user

I have no symptoms of hanging

If I close all my FF copies then I see no evidence of FF running in Task manager I can start the default profile automatically or indeed any of the others either by the short cuts or via the shortcut that takes me to the Profile manager ie the shortcut "C:\Program Files\Mozilla Firefox\firefox.exe" -P However this has started the default Firefox running so you can't start the default version this way. One can see the exec in task manager.

I believe that I now have everything working to my satisfaction and thanks for your help.

You're welcome.

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