Please start *Windows'* safe mode with networking enabled - win7 https://support.microsoft.com/en-us/help/17419/windows-7-advanced-startup-options-safe-mode#start-computer-safe-mode=windows-7

Still In Windows safe mode, start thunderbird in safe mode - https://support.mozilla.org/kb/safe-mode-thunderbird

Does problem go away? Please reply to let me know results.

Thanks so much for the help! I started up in both safe modes and worked on posteo for about 10 minutes in safe mope trying different size emails and the like and it didn't freeze up although I don't know how much longer that would last.

So assuming that this was the resolution, what do I do to maintain it once I am no longer operating in Windows Safe mode?

Thanks for doing that, and for asking.

So the decision tree that comes from the two safe modes is ....

- If problem did not go away, then cause is either: bug in Thunderbird, in your Thunderbird profile, your mail provider. Please post into topic the contents of Help | Troubleshooting | copy text to clipboard

- If problem did go away, (still in Windows safe mode) ... start Thunderbird normally -- If problem is still gone, then cause is a program loaded during windows startup. Possibilities include: antivirus SW, virus/malware, background downloads such as program updates -- If problem is came back, then cause is likely a Thunderbird addon - eliminate them by disabling each one at a time in Tools | addons | extensions and restarting

- If results are unclear ... possibilities include temporary conditions such as contention from other running programs, downloads related to windows update, ...

A monolithic list is https://wiki.mozilla.org/Thunderbird:Testing:Memory_Usage_Problems

Please let us know your findings.

Thanks for the continuing help. But I am confused by exactly what this means: - If problem did not go away, then cause is either: bug in Thunderbird, in your Thunderbird profile, your mail provider. Please post into topic the contents of Help | Troubleshooting | copy text to clipboard If you can clarify then I can try to go further with this. Thanks again

helpappreciated said

Thanks for the continuing help. But I am confused by exactly what this means: - If problem did not go away, then cause is either: bug in Thunderbird, in your Thunderbird profile, your mail provider. Please post into topic the contents of Help | Troubleshooting | copy text to clipboard If you can clarify then I can try to go further with this. Thanks again

Did your problem totally go away when starting both Windows and Thunderbird in safe mode?

If it did go away, then do Help, Troubleshooting, copy text to clipboard and post your clipboard into this topic