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My Thunderbird 62.0 for windows 10 is using1.9 MB and 80% CPU. Is there a memory leak

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My Thunderbird 62.0 for windows 10 is using1.9 MB and 80% CPU. It hangs freezes and crashes, and there is an annoying 5 second delay between my keyboard and monitor. Links usually take 2 minutes to come up in Firefox. I have tried safe mode and although it is better, it still uses 65% CPU and around 1.2 MB memory.

Is it just me or are there others having this problem? Any suggestions? Should I install an earlier version of TB?

My Thunderbird 62.0 for windows 10 is using1.9 MB and 80% CPU. It hangs freezes and crashes, and there is an annoying 5 second delay between my keyboard and monitor. Links usually take 2 minutes to come up in Firefox. I have tried safe mode and although it is better, it still uses 65% CPU and around 1.2 MB memory. Is it just me or are there others having this problem? Any suggestions? Should I install an earlier version of TB?

All Replies (6)

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Hello there we have receive the message.



Can I ask you a few questions? Is this only the case when running TB? Are all other programs defective? What kind of computer do you have? Is this a recent one?


Firefox volunteer.

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Yes, this only happens when running TB. I have an HP TouchSmart 300 with 4 GB RAM, on a Windows 10 Home 64 bit Operating system using an AMD Athlon II 235e processor. I've had it for about 5 years. All other programs run fine as long as I don't have TB open. If TB is running any Application will take 1 to 2 minutes to launch and within a few minutes either TB or the application crashes (usually TB). Any help will be appreciated. Thanks, Gaby

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re :I have tried safe mode

This sounds like you are refering to Thunderbird Safe Mode.

Could you restart the computer in 'Safe Mode with Networking' mode and then start Thunderbird as normal. Please post results.

What Anti-Virus product are you using?

How many mail accounts (email addresses) are in Thunderbird? Are they IMAP ? Do you subscribe to see alot of folders? What size are your mail account folders?

I notice you mention: 'My Thunderbird 62.0 ' The latest release version is 60 I'm not even sure that a beta version of 62 has been created, so please check what version you are using and post info. Help > About Thunderbird

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re :t hangs freezes and crashes,

Hangs and freezes could be another program like Anti-Virus performing a load of scans. Crashes should be logged, so please post the following Information: In Thunderbird

  • Help > Troubleshooting Information
  • Do Not select the checkbox to include account names.
  • click on 'Copy text to clipboard' button
  • In this forum question, right click in a 'Posta Reply' text box and select 'Paste'
  • Please remove all info on fonts and printers, but do not edit anything else.
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We didn't ship a version 62.

And you probably mean 1.9GB, not 1.9MB?

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Thank you for using. Firefox.

Firefox volunteer.