Add-Ons

[gillyanna]

A recently installed programme is trying to use an add-on in Firefox. When I go to Firefox, Add-on appears in the address box, and a message asking me to instal it appears on the main screen and says I can change my mind by using add-on manager (which I can't find anyway) However there is no tick box for me to say yes or no. and almost as soon as this message appears, Firefox disappears. It happens every time so Firefox is essentially disabled. I have scanned and cleaned the system to no avail. I don't know which programme is responsible. Any ideas?

[bazwillrun]

What version of FFox ? Help>About
What add-ons do you have Tools >Add ons then Extensions and Plug-Ins
What software have you recently installed ?

[hc4361]

Uninstall Firefox and then download the latest version