Unwanted pop up .

[modeller]

Every time I boot up within a minute up comes the window which says someone is trying to access your PC
Followed by the options Allow and Not Allow cancel and underneath Details . Now this as you know is quite common and if you click Not Allow thats the end of it but with this one whatever I click on it just disappears until the next Boot up.
I think it first appeared when I up-graded Firefox so I decided to uninstall Firefox completely, with dire results I couldn't open any of the sites on my Desk-top with exception of IE which I used to install the lost sites and put the shortcuts on the desk top, but no good they didn't open.
I re-booted and was pleased to see the unwanted pop up didn't occurr which rather prooved FFox was to blame. However I still couldn't open any of the lost sites. I had no option I reinstalled FFox and everthing worked again but also back came the pop up. Any ideas of the problem ? I now think FFox made itself the default browser. Would that cause my problems. ? My OS is Vista.

[ChuckFickens]

look for an option to remember this setting and click allow

it's perfectly normal for a firewall to ask about a browser after it's been upgraded.

[modeller]

I did but as I have said nothing happens , the window just disappears the window just comes up again the next time I boot up. I should point out the identity of the requester is marked unknown . Quite simply if I allow it, nothing happens and if I cancel it nothing happens, the window just comes up next time I boot up. It may have nothing to do with the browser I just thought there might be a connection.