- Joined
- Oct 16, 2010
- Messages
- 18,172
- Reaction score
- 1,918
- Points
- 113
- Location
- Brentwood Bay, BC, Canada
- Your Mac's Specs
- 2020 27" i9 5K nano iMac, 1TB(partitioned) SSD, GB, macOS 15.3.1 Sequoia
iMac mid 2010 / macOS Sierra V 10.12.6
A rather old one ...
That iMac model could go up to macOS 10.13: High Sierra, but I doubt very much if it would improve anything. In fact, it might even make it worse.
iMac "Core i5" 3.6 21.5" (Mid-2010) Specs (Mid-2010, BTO/CTO, iMac11,2, A1311, 2389): EveryMac.com
Technical specifications for the iMac "Core i5" 3.6 21.5" (Mid-2010). Dates sold, processor type, memory info, hard drive details, price and more.

Have you not tried using Mac Mail.app and does it not work for you???
Why are you insisting on using Thunderbird, especially when it doesn't seem to be working??? ?
- Patrick
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