What is alert 8508?
A user or script has sent an email to an unknown host called Undefined. They could be one of:
- A user from the GMS Webmail interface;
- A user logging on to the Administration interface;
- A script (e.g. a user script, custom MML script, list script).
The return code from gethostbyname was Undefined.
The session id was Undefined.
No further action is required by you.