If you happen to be using the Firefox Preloader, you will need to turn it off.
If not, try looking in your services (Ctrl + Alt + Del), click on Processes and scroll down the list and see if Firefox is running, if it is, you will need to select it and end the task.
I just done a google search for the error message in your screenshot, looks like it also may be a problem with profiles. If so, you will probably want to uninstall Firefox and then BEFORE you reinstall, delete the Firefox folder, do a Disk Cleanup (use CCLeaner) and try it again.
hey i am get a error ever time i lunch it try restatring and reinstlling fire fox still i get the error heres a scren shot of it http://img157.imageshack.us/img157/5469/help6gr.jpg

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