I am getting complaints from links that Firefox is already running and needs to be closed when it is not visibly running. But, I do find it as a process that IS running. What gives?
I click on a link in an E-mail. It complains that Firefox is already running and I must close it. Firefox is NOT visibly running. I check via Task Manager to verify. I find Firefox is running as a process. I kill the process and then can proceed. I did use Firefox earlier and closed it.
Opaite Mbohovái (1)
Make sure that you do not start Firefox with the -no-remote switch or have set the environment variable MOZ_NO_REMOTE=1 (Control Panel > System > Advanced > Environment variables).
If you need to have more than one profile open at the same time then start subsequent instances with the -no-remote command line switch.
You can send links from other programs to a Firefox instance that is started with -no-remote, you need to drag links in a Firefox window in such cases.
See http://kb.mozillazine.org/Opening_a_new_instance_of_Firefox_with_another_profile