I am using Windows Vista. Firefox used to connect fine until a couple of months ago when I downloaded a windows update - then it broke, so I tried undoing the windows update but it is still broken.. Someone told me this issue is connected to a telnet issue so I tried installing telnet and sure enough I cannot connect using telnet to any servers on any ports. I think this also may be causing a problem I am having with Skype lately but there may be another factor involved in that too.. At first I was told this was a firewall or router problem. But I have eliminated both those possibilities - I turned off the firewall completely and I have tried connecting direct to the internet, and even from a different wifi network, still the same issues. Also, on my home wireless network, my server (windows 2003 server) connects fine with telnet, mozilla connects fine and so does skype. Help, as this is meaning my laptop is virtually useless to me and has been for two months. I have had to turn down a lot of work due to this problem and its really annoying me now!!

I should add that ping works fine.. and popup blockers and addons have all been disabled.. I also tried removing skype completely (including registry settings and all files) and going back to a previous version of skype just in case skype was the problem, to no avail.. I have restarted the pc lots of times, and the router too.. I think I have a lot of symptoms in common with this posting http://social.technet.microsoft.com/Forums/en-US/itprovistaie/thread/2c31cb4e-119b-443b-8058-099106d84435

I turned off all the processes that are not essential windows services using msconfig too by the way - so it is not another antivirus product or hp product or whatever - still the same problem

also Yahoo! Messenger and IE8 have worked fine throughout all this

Also tried resetting winsock and no change

Hi, Could you specify which windows update is it? In case certain components of mozilla firefox became corrupted, I suggest reinstall it to check the result. If the issue persists, you can go to device manager, right click on the network card, choose Uninstall. Apply the settings and restart the computer. Meanwhile, as this issue only occurs to mozilla firefox, their support (http://support.mozilla.com/en-US/kb/) would better be involved. Please Note: Since the website is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information. Regards,Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.