Are you stating that emails to you show 'Me' as the recipient? If so, that might be because you have that specified for you in your addressbook. In settings, you can specify to NOT use addressbook names on email messages and that should revert to showing just email addresses.

See https://support.mozilla.org/en-US/questions/1332448

Settings/General, Config. editor.

Thanks for the responses but unfortunately no luck. I should have mentioned I am using the current version of Thunderbird.

I did find this checkbox: Show only display name for people in my address book Checking/unchecking has no affect, and yes I reloaded Thunderbird between tests.

mail.showCondensedAddresses is/was already assigned to false.

I'm at a loss :(

Thanks for the suggestions.

Do you have your own address in Address Book?

Do you have your own address in Address Book?

Yes, I have multiple addresses that appear in the address book. Testing with different emails, to cc etc.: Sometimes the To will be prefixed, sometimes the Cc and sometimes both.

It is a long time since I have heard of pretty names. I even wrote a blog post about it back in 2010. None if the screens look anything like now, but the option is still the same.

Open settings, search for display Turn off the option to "show only display name for people in my address book". That is also the user interface provided to toggle the hidden preference mail.showCondensedAddresses

So really I don't think the research has identified the real issue here. Do you see similar results when Thunderbird is running in troubleshooting mode? (continue when prompted) Are any of the accounts hosted on an Exchange server? (Microsoft take this stuff to extremes at times)

Open settings, search for display Turn off the option to "show only display name for people in my address book". That is also the user interface provided to toggle the hidden preference mail.showCondensedAddresses

I've tested it checked and unchecked the "show only display name..." option, no difference. The mail.showCondensedAddresses is false.

On one of my tests, I moused over the email and selected edit. There it was.. the display name said "Me". So I changed it to a more vulgar name that suited my mood at the time. Saved it, cleared Thunderbird cache, closed Thunderbird, rebooted my desktop....

Ran a test and...."Me" still appeared.

As you suggested, I turned on the trouble shooter. Sent a test and the results were exactly as they should be, without the "Me" Turned off trouble shooter and "Me" was back :(