I cannot edit, see below
and: I have 64 RAM, not 16
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Thanks a lot, that was exactly what I was looking for.
yes, I used the Migration Assistant
The old one is v5
the new one is v9 w/o the old v5
In the meantime I already used the new mac mail app, incoming and sending, now I wonder: if I copy v5 and rename it to v9?
Or should I copy only the older mails from v5 into v9?
created date - or - modify date ...
I did compare the names of the newest folders in user-library-mail
there are similar names - looks good
I could copy old to new via chronosync
I will start a test with just one small folder to test
I must admit, I had lots of subfolder in mail that were not used in the last 6 months and thus did not exist after moving, like xmas greetings, register of apps, etc.
So I created them manually, hope this does not make problems
then I will restart the mail for a refresh