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Thunderbird running slow and slowing down all other Win 7 processes, after upgraded from office 12 to 14. CAUSE unknown

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  • Last reply by Wayne Mery

BBands
BBands
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I have two instances of Thunderbird, both configured the same way, one on Win 7 Pro and one on Xubuntu, both 64 bit. The Xubuntu instance is running near perfectly, but the Win 7 version is running very, very slowly and hanging other programs. For example, composition is nearly impossible. I have 4 cores and 8 gb ram. This started when I upgraded from office 12 to 14. I have tried all the safe mode stuff to no avail and have uninstalled and reinstalled Thunderbird. The system is fine otherwise. Any clues?

I have two instances of Thunderbird, both configured the same way, one on Win 7 Pro and one on Xubuntu, both 64 bit. The Xubuntu instance is running near perfectly, but the Win 7 version is running very, very slowly and hanging other programs. For example, composition is nearly impossible. I have 4 cores and 8 gb ram. This started when I upgraded from office 12 to 14. I have tried all the safe mode stuff to no avail and have uninstalled and reinstalled Thunderbird. The system is fine otherwise. Any clues?

Modified by Wayne Mery

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Wayne Mery
Wayne Mery
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See https://wiki.mozilla.org/Thunderbird:Testing:Memory_Usage_Problems

Wayne Mery
Wayne Mery
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> Reporter writes "Thunderbird is still experiencing severe problems as described before. Have taken all suggested actions, empty trash, spam, compress, etc to no avail. Linux instance still working perfectly with same configuration. Have had to switch to eM Client for windows in order to be able to work; same configuration and working fine. "

A frequent cause is antivirus or other software. Somewhat at the bottom of the list in terms of frequency is a bad folder index (which can be fixed in Thunderbird by properties > "repair". In between are the many possibilities listed at See https://wiki.mozilla.org/Thunderbird:Testing:Memory_Usage_Problems - which bbands says does not help - and more.