I've been getting this problem too. It's extremely annoying, looking at switching browsers...

Firefox can't load websites but other browsers can

Check and tell if its working.

Same here. This problem started after the 7.0 upgrade. Was hoping the 7.0.1 fix would resolve the issue but it didn't. I even completly uninstalled the program (with the exception of my prefrences) and installed fresh, 7.0.1, same issue.

This is VERY annoying and has caused me to switch back over to IE.

Tried the resolutions from the link.

Internet Security software blocking Firefox - Does not apply. Sites can be accessed but over a given amount of time, those same sites are no longer accessable unless I restart FF.

Firefox connection settings - Does not apply. No proxy server is being used.

IPv6 - Made the change, did not work.

DNS Prefetching - Made the change, did not work.

Firefox cannot load certain websites - Cleared everything, problem still occurs.

Check for malware - No malware found.

Exact same problem here since upgrading to 7.0. I've been searching for solutions for the past few days and all of these suggested solutions have NOT worked:

• clearing cookies and cache
• starting Firefox in safemode with all add-ons and plug-ins disabled
• uninstalling and re-installing
• going to about:config and resetting all network preferences to defaults

I too was hoping the update to 7.0.01 would address this issue but it hasn't. I'm so fed up at this point and will (very reluctantly after being so happy with Firefox for all these years) be switching browsers, because Firefox is pretty much unusable in its current state on my machine.

@mha - Tested the solutions in that link, did not solve.

As best I can tell, it almost seems like one element on the page throws FF for a loop, at which point it halts all other connections indefinitely. Very strange behaviour.

Even turned off the firewall, still having issues.

Come on mozilla, we all know you are aware of this. Fix it!

I also have this problem and I am so surprised that there are not more people complaining about this. This was not even caught during beta testing? Firefox has been going downhill since v4 for me. It gets more and more unstable even with addons disabled. No wonder more and more people are leaving Firefox.

I may have found a solution to this problem here (well, at least Firefox has been working again for the last few hours, not sure if it will prove to be a long term solution or not).

As it says in the linked article, type about:config into the address bar, find network.http.max-connections and change its value from 256 to 48.

I have absolutely no idea why this works but it seems to. According to my resource monitor Firefox still seems to be using a ridiculous amount of memory and disk, and my cpu fan is still going crazy, but at least websites are loading again!

Does this fix the problem for anyone else?

@archeocyathan

Good find, thanks for posting! Still very odd..

I've now set network.http.max-connections to 64. We'll see how that goes.

edit: Tested a few different values and 48 seems to be the magic number. Anything higher starts causing problems for me, although 64 was much better than 256, and anything 48 or less works fine.

Thank you for the very helpful solution. I changed the settings from 256 to 48, restarted Firefox and now all pages are loading like they used to prior to Firefox 7.0 and 7.0.1. Appreciate the help!

I tried changing the setting from 256 to 48. After a restart it appeared to be working, but then the 15-30 second pauses came back!

I had high hopes this would work, but it does not get rid of this problem!

Having the same problem, here is some info for those of you capable of discerning the root cause:

1. Problem started after recent automatic Firefox update. The problem was not noticed at all prior to this.

2. CPU usage is normal until a search is performed. I currently have 6 tabs opened via bookmarks with CPU usage sitting at 0% for firefox.exe right now. 3. Once a search is performed, loading a page from the search may execute normally or it may not. This is where the problem occurs. If Firefox does not load the page in a normal fashion, CPU usage rises to 49% - 55%. After closing the offending tab and the search results page only reduces the CPU usage to 50% and never goes below this until the Firefox process is ended (see #6). Once Firefox enters this state, memory usage slowly climbs and continues to do so and periodically drops, but never below the level reported once the CPU usage goes to ~50%.

4. Using IE v8, I opened the same tabs and performed the same search and opened the same site that hung Firefox without problem, with CPU usage never reaching 50% at any point and returning to 0% - 5% after page loading.

5. I duplicated these results with antivirus (Spyware Doctor w/Antivirus v8) disabled. EXACTLY the same results experienced.

6. I have closed all Firefox tabs except this one and CPU usage is still at 50% - 52%. I closed the Firefox browser completely with task manager opened and watched. The Firefox process never ended and CPU usage remained at 50% until I manually ended the process. I then reopened Firefox (without rebooting or any other adjustments), it automatically came back to this page and total system CPU usage is at 1% - 3% with firefox.exe showing 0% CPU usage.

7. Prior to all this testing, I downloaded and reinstalled Firefox. I cleared my Firefox cache and my Windows temporary files. This made no difference in the results. Google was the search engine used in both the Firefox & IE tests. My system runs Win XP SP3, 2gb of RAM.

This appears to me to be a search related memory leak. I am more than willing to do some more testing if someone things they have a viable solution.

moderator fixed the line breaks

I have the same problem since updating to 7.0.1. After reinstalling Firefox 6.0 everything works fine again. Tried this "change" several times, always the same result...

I'm having this problem here since FF 4.0 (I use Portugue - Brazilian). I've been trying new versions since FF4.0 and because of memory consunption and constant hangs, I always go back to 3.6.18. I've changed network.http.max-connections to 48 @ FF7.0.1 and will test it. Hope further versions have this fixed cause Firefox used to be way better than all the other browsers in the past

I have the same issue here. Ever since the auto update for 7.0.1 I've had the issue where the sites loading hang for a good amount of time. This is appears to be a big issue. Please fix!

Hi! I'm a Firefox developer. We're trying to figure out what's going on here. Previously, this has been caused by third-party software in DLLs (libraries loaded into Firefox that we don't control). See, for instance:

 https://bugzilla.mozilla.org/show_bug.cgi?id=681198

We suspect something similar might be going on here. If we can get some users to give us a list of the DLLs that are running in firefox.exe when you see this hang, that would be *very* very helpful.

To help:

1) Reset your network.http.max-connections back to the default (256).

2) Download Microsoft's "Process Explorer" software:

 http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx

3) Browse with Firefox until you see the hang, then report the list of DLLs you see to us. The best way to do this is to file a comment in the bug report we have open for this, here:

 https://bugzilla.mozilla.org/show_bug.cgi?id=692260

(You'll need to create a bugzilla account: takes just a minute!)

If you need step-by-step info on how to get the DLL list with Process Explorer, follow these instructions here (except for firefox.exe, not outlook of course :)

 http://support.microsoft.com/kb/970920

Thank you! It sucks to see an issue like this slip through 12 weeks of testing :( I hope we can fix it ASAP with some of your help.

best,

Jason Duell

Dev release 8 seems not to have the problem. But it killed tab dragging! Which is a PITA.

Actually, 7.0.1 had the tab problem too.

I am almost certain this problem is connected to flash.

The reason i think this a lot of the time i have this issue flash is on the website and the flash doesnt load and when i go and try and go onto a different site the page just hangs.

I could be wrong tho but im having the problem to and its so annoying!