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Firefox running slow, even after resetting AND reinstalled

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For the last several days Firefox has been running really slow. When I open a new window it takes about 20 - 30 seconds to open one or if I try to load a site with flash (say such as youtube) it takes about about the time to load the site and you can't click anything, such as back, address bar or even the X to close the window.

I've scanned for viruses and found nothing. I thought it was my computer when Firefox first started to go slow but I opened up Opera and Saferi to see what they was like and they are fine. Runs very smoothly. If I restart the computer Firefox will work great for say 2 hours before it starts to slowly slow down again over time (by about 5 hours later it's uber slow again!). I've also reset Firefox which again gave the same result as restarting the computer, fine for a couple of hours before starting to slow down again. Reinstalled Firefox but there again it's fine for a couple of hours.

I don't know what to do. Firefox is my main browser but I can't keep using it like this because it's taking forever to do anything.

For the last several days Firefox has been running really slow. When I open a new window it takes about 20 - 30 seconds to open one or if I try to load a site with flash (say such as youtube) it takes about about the time to load the site and you can't click anything, such as back, address bar or even the X to close the window. I've scanned for viruses and found nothing. I thought it was my computer when Firefox first started to go slow but I opened up Opera and Saferi to see what they was like and they are fine. Runs very smoothly. If I restart the computer Firefox will work great for say 2 hours before it starts to slowly slow down again over time (by about 5 hours later it's uber slow again!). I've also reset Firefox which again gave the same result as restarting the computer, fine for a couple of hours before starting to slow down again. Reinstalled Firefox but there again it's fine for a couple of hours. I don't know what to do. Firefox is my main browser but I can't keep using it like this because it's taking forever to do anything.

All Replies (4)

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Chosen Solution

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Thanks for that. Made a new profile and it got back to normal (running smoothly) but didn't like it without all my history and everything gone (had alot of stuff i needed) so I switched back to my old profile and that too was fine.

When it starts to get slow, all I do is reload with the new profile then change it back and it's all fine again for 3+ hours. Might not be an ideal fix but it keeps my data without having to move it to a new profile or anything and it only takes like 10 seconds to do so i'm happy with that!


Thanks for your help!

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Firefox saves your personal information such as bookmarks, passwords, and user preferences in a set of files called your profile.

you can restore your old data from your old profile. Just Back up from old profile and restore to new profile.

Profile Backup and Restore

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This new version 31.0 is dead slow.

For instance, I opened About Firefox to check the version number, and the popup pane was stuck for about 15-30 seconds, which it "checked for updates" automatically.

Any dropdown menu opens slow & the keyboard buffer seems slow - having trouble typing this. Appearing on the screen is seconds behind my input.