Hi Guys
I promised you an update and here it is:
1.) on the v10 Test Server i removed letsencrypt -> server-manager allso no more reachable
2.) i deinstalled and reinstalled the sme openssl -> server-manager AND webmail works again perfect
I think ReetP's advice to regenerate letsencrypt's certificate with dehydrate -c should then fix the problem in productive mode.
For now in testing use in the V10 the selfsigned certificate is OK for me.
Now another question:
Do i have any chance to connect to my intranet testserver by IMAP client on a internal ip instead of mail.myserver.com:993 ? I tried by 192.168.x.x but it looks as the sme V10 Testserver doesnt allow a such connection. The same is i want to test the websites allso in intranet mode. This maybe i can solve over proxy resp. gateway settings in browser.
Btw, big respect what you are doing here.
I give my word that after successfull migration and stable working of my V10 in productive mode, i will push the donate button.
stay healthy and thank you again !
umbi