Nagios Support Forum

There indeed was a different in /etc/postfix/main.cf
This is quite a long file so was not visible in the console (if that's an excuse).
myhostname, mydomain and myorigin has now been corrected. But still no e-mails.

Admin > Email Settings have Sendmail selected on both the old and new host.
II can configure both Sendmail and SMTP and this both doesn't work

It's been a lot of digging (I did not set this up myself and there was no documentation on it) but apparently it's using PHP PEAR to send e-mails with custom templates.
And PEAR was not installed to it did not work. Now it's installed and the system started e-mailing again!

Hi

Thanks for the update. We're glad you got it working again!

Thanks