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Ever since I installed the latest update, TB freezes and uses 100% of my CPU. Why? Same in safe mode, nothing else has changed or updated.

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I have now new software updates other than TB. At first, after about 10 minutes, I would get a pop-up window telling me that a script is unable to run and Flash is the issue. I removed Flash and the problem still exists. I've never seen any mention of scripts running in TB before.

TB safe mode doesn't help - same problem.

Windows XP safe mode doesn't help, either

I have now new software updates other than TB. At first, after about 10 minutes, I would get a pop-up window telling me that a script is unable to run and Flash is the issue. I removed Flash and the problem still exists. I've never seen any mention of scripts running in TB before. TB safe mode doesn't help - same problem. Windows XP safe mode doesn't help, either

All Replies (13)

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I did a complete reinstall of Thunderbird about an hour ago and the problem is worse than ever. Does an older version still exits for download?

It would be nice if someone at Mozilla addresses this problem and not ignore me.

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Okay, here's what I have so far - if TB is open with nothing else, it seems to work for a while. If I have Firefox open at the same time, TB suddenly starts using all the CPU in about a minute or two, completely choking my system.

I try to keep both open so I can get my mail while doing other things. This is now a major headache for me, making it impossible to quickly respond to emails or even compose an email longer than a few words.

Anybody out there who can help me before I go to another program for my email? I like TB up until now. I've been using it for years.

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Actually, it is worse. Even if TB is the only program running, it still ends up using 100% of my CPU and freezes after a few minutes.

I need help here.

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Here's the "script" that is causing the hanging:

chrome://messenger/content/folderPane.js:503

How do I get rid of this problem? This is an urgent problem to fix.

Does anyone from Mozilla ever look at new questions?

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It's definitely something wrong in the latest version of TB. I installed SeaMonkey, which is also Mozilla based and the problem is gone. I didn't want to use new software, but the lack of response made it necessary.

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I'm completely done with both Thunderbird and Firefox. No response to my TB problem and now the latest version of Firefox is doing the same thing - using all my memory and constant script freezing issue. I've had a number of friends call me with the same problem.

Bite me, Mozilla.

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What is your anti-virus software?

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Ad-Aware Free. I tried running it with Ad-Aware shut off and it made no difference.

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Does it have something like 'network & email protection'? If so disable that. Don't let it scan your Thunderbird profile folder. Don't let it scan incoming and outgoing attachments. Don't let it intercept your secure connection to the server.

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As I said, I completely shut off Ad-Aware. It wasn't scanning anything. It made no difference. I even tried TB in Safe Mode with Ad-Aware off and it made no difference. I've never had it scanning my email.

I've been using both for years with no issues, until the latest TB update.

I think there is something in the base code since the latest FireFox is doing the same thing.

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Here's something else for the non-existent help from this forum.

I just installed Thunderbird on a brand new computer. No anti-virus running, nothing else.

Same exact problem, same script causing the problem.

Why is it that too many sites now have absolutely no useful support at all?

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Lets see, millions of users have no issue. So is there an problem in the code. Perhaps. is the cause external to Thunderbird probably.

Your identifying a script and hanging your hat there. Thunderbird and Firefox basically have their entire user interface written in javascript and it is very time conscious so if something is causing high CPU utilization then you will see time out errors. The script you identify is the one that draws the three panes you see in Thunderbird with folders and mail lists.

Have you actually rebooted XP into safe mode with networking and tried running Thunderbird in that mode to see if it affects things?


You are using windows XP. This operating system has unpatched and exploited in the wild vulnerabilities. Todays is https://blog.gdatasoftware.com/blog/article/poweliks-the-persistent-malware-without-a-file.html

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Did the XP in safe mode with TB in safe mode and the same thing happens.

I'm well aware of the new Windows vulnerabilities. It goes well beyond XP all the way to 8.1. As a precaution, I ran a full anti-viral scan today with updated definitions. I also ran Malwarebytes with updated definitions. Neither came up with anything.

Did you notice that I said I installed TB on a new machine, Windows 7. Nothing else is installed on it yet other than what came with the computer. TB has the same problem.

I'm also going to see if SpyHunter with updated definitions finds anything on the XP machine. I think I have one other thing to try to seek out a problem.