Windows 7: An instance of this prog is already running

An Instance is already running
Hi all, first post here new member good forum. That said I am running win 7 pro 64. I have an application named freightmaster on my machine which has multiple users on it. Lets say there are 5 users. It was all running fine for some time.

Now on 3 out of 5 users the application just runs in memory when launched and pins to the taskbar, when I try to open it from there I get "An instance of freightmaster is already running, please close this down before starting a new session.
Facts are ... I do not have any other instances running on any other user as I have them all logged out when I launch it. The icon is from the public desktop and it is only run by clicking the icon. I watch in taskmanager and yes a second instance of the application does run in mem when when I try to maximise the first instance from the taskbar, although it never "fully opened" in the first place.

Anyone had this sort of thing ?

Thanks heaps ozzie

Can you unistall and they try to install again? If you use this option use ccleaner after the uninstall and uninstall using revno. If it does not happen frequently, you could just close the second instance.

http://www.revouninstaller.com/

Check in Task Manager whether a process of the program is rumming and if yes, kill it right there.

No can't uninstall it because it's highly configured by a third party and it's difficult, and no it's not already running before I launch it as I have Checked task list and checked all users tasks. I can observe that there is one instance started when it's launched and then it "minimises on taskbar" trying to open it from there gives the error as this starts a second instance of the app FMGui.exe

Yeah what he says

I have same problem with Windows Media Player all the time

what is the nature of the problem?

WMP doesn't close after I've closed it down - in fact in some cases the music just keeps playing - i have to open it again, stop the music then close it - in most cases tho, after closing it, it will not open at all - look in the task manager to find it's still running and you have to close it from there before it will run properly again