FireFox 3.6.10 periodically loses the internet connection. Following Mozilla advice I contacted my firewall vendor, Norton (360). They set "allow" for the rules for FireFox, Thunderbird, and IE. The problem remains. Why?
I have DSL service to a wireless router. I use a wireless connection from that to my computer. Periodically, and almost certainly within about 15 minutes of launching FireFox, my browser loses the internet connection. But my wireless connection remains solidly "on" and tells me I have internet connectivity. During this period, I can still use the internet to do sftp transfers, so I'm confident it is not a router problem. I can "refresh" the browser's connection by momentarily disabling then re-enabling the wireless connection. That seems to awaken FireFox within a minute or so and it resumes reading the internet. Occasionally, Thunderbird has similar problems.
Opaite Mbohovái (3)
I'm up to FireFox 3.6.13 now and the problem is happening more and more frequently.
Create a new Boolean pref with the name network.manage-offline-status and set the value to false.
Right-click on the about:config page to open the right-click context menu and use "New > Boolean" to create a new Boolean pref.
Name: network.manage-offline-status
Value: false
I've had this problem for a few days. I assumed it was my router so I've been disabling and re-enabling the connection via the router software. This method has been working though it has been taking absolutely ages to load each page in the router interface.
Then for some reason it occurred to me that it might be Firefox so I tried another browser and hey-presto - no connectivitiy problem . So I Googled, found this page and saw the suggestion above. I just tried a much simpler fix which worked for me (don't know if it will continue to do so). In Firefox, select File > Work Offline to go offline, then File > Work Online and problem solved - for me at least.
Hope this helps someone.