Question posted in 
I’m out of options. After using the WHM transfer tool to copy my entire cpanel account to my other server for testing (did that several times without problems) there were a lot of problems, als see
https://forums.cpanel.net/threads/transfer-tool-issues.678209/
After changing back the .htaccess the site was up-and-running again. Also i did the dovecot and exim reset. Mail is sending, but incoming mail is a problem. It seems that there is a redirect or something only for incomming mail. I get this faults:
Cpanel mail
SMTP error from remote mail server after RCPT TO:[email protected]: 550-Please turn on SMTP Authentication in your mail client.n550-cloud.tricotstoffen.nl [31.186.173.214]:50078 is not permitted to relayn550 through this server without authentication.
Bounced mail (hotmail)
host cloud.meisjemeis.nl [31.186.173.208]
SMTP error from remote mail server after RCPT TO:[email protected]:
550-Please turn on SMTP Authentication in your mail client.
550-cloud.tricotstoffen.nl [31.186.173.214]:48250 is not permitted to relay
550 through this server without authentication.
The last one contains the wrong host (cloud.meisjemeis.nl is not the correct one)
3
Answers
For some reason the /etc/manualmx was changed. Setting the correct value did the job
Follow the below step to solve this issue.
->login in Cpanel account.
->Type "Email Routing" in the search bar or find it in the "Email" section.
->On the next page, choose your domain from the drop-down list.
->Once you’ve selected the domain, you will want to make sure it’s set to "local mail exchanger", then click change.
Obviously, if the domain is already using the "local" option, you don’t need to change it.
we created new dev server, but mail troubleshooter in whm was pointing to new server, this answer helped me to fix the issue