Thunderbird Download Issues
Thunderbird can have problems with POP protocol download issues of large emails
Thunderbird can experience problems downloading POP emails of over 5MB (or over 10MB).

This problem seems to only happen with Thunderbird past version 45. It definitely happens with version 52 and 59.

Simply finding the setup exe for Thunderbird 45 (from the Mozilla website) and running it will install ver 45 and keep most of your settings.

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