Symptoms
- Emails go to the Spam folder instead of the Inbox folder when the DKIM spam protection is enabled for the domain in Plesk > Domains > example.com > Mail Settings > Use DKIM spam protection system to sign outgoing email messages.
- DKIM is marked as Fail in by email services, for example, Gmail or Hotmail.
Cause
DKIM record is corrupted.
Resolution
- Log into Plesk
- Go to Domains > example.com > Mail Settings.
-
Create New DKIM Selector > Set Selector Name as test > Create
- Under Active DKIM Selector select the radio toggle for test > Apply
- Under Active DKIM Selector click Remove for default > OK
- Repeat the same steps to create a new default DKIM selector and delete the test
Create New DKIM Selector > Set Selector Name as default > Create - Under Active DKIM Selector select the radio toggle for default > Apply
- Under Active DKIM Selector click Remove for test > OK > Apply.
Note: on Plesk for Windows the DKIM record is recreated instead of regenerating, this is enough for the case when the DKIM record is broken.
Note: is DNS is hosted externally, manually copy default._domainkey.example.com record to the external DNS server
How to apply on Plesk 18.0.55 and Below
- Log into Plesk
- Go to Domains > example.com > Mail Settings.
- Disable the Use DKIM spam protection system to sign outgoing email messages option.
- Press the Apply button.
- Enable the Use DKIM spam protection system to sign outgoing email messages option.
- Press the OK to button to generate a new DKIM record.
How to Update default DKIM for ALL Domains at once via CLI
Running the following command can be dangerous as it will update every single domain in Plesk at once. This command will also Delete all current Default DKIM keys for ALL Domains on Plesk and reissue a new default domainkey while Enabling DKIM signing for ALL Domains. It is important to note that during the time it takes for this new DNS Record to propagate out, DKIM will fail till propagation completes.
If DNS is Hosted Externally for a Domain, this Command will break DKIM. You will need to manually copy this DKIM record into your External DNS Server. More on this here - https://support.plesk.com/hc/en-us/articles/12377243733015-Outbound-emails-do-not-pass-DKIM-verification-when-DNS-is-hosted-externally
- Log into Plesk
- Open SSH Terminal Extension
- Create a Plesk DB Backup
- Run the following command:
# plesk bin site -l | while read name; do plesk bin domain -u $name -mail_dkim false && rm -f /etc/domainkeys/$name/default && plesk bin domain -u $name -mail_dkim true; done