My VPS have Ubuntu 18.04.5 LTS and ISPConfig 3.1dev installed. For some time now, outgoing emails no longer show DKIM signatures. What should I check to fix the problem?
Firstly, update to 3.2. It's not a good idea to run dev versions in production. It might have been that there was a problem in the dev branch when you installed that version, that causes this. Make sure you reconfigure services when upgrading. You can update by running Code: sudo ispconfig_update.sh If you still experience this issue after updating, check the DKIM settings under Email -> example.com -> DKIM.