In PM, click > Tools / Options / Advanced / General tab / and at the bottom, click the bar to make PM your default browser.
Am guessing you never specified a default browser after making the switch to PM, and that should fix your problem.
If not, there's prolly a similar option that needs checked in your email app to point it to PM instead of FF.
That fixed it thanks, I love freepers always there to help the technologically impaired.