How do I match an empty subject line in an Outlook rule?

Question

I would like to create a rule in Outlook (2011 for Mac) to match on a empty subject line and return a message hinting that it would be better to include an informative subject line next time. (Yes, it is a try to use a technical solution for a social problem.)

I'm not able to add a rule with "Subject", "is" and then leave the text area empty. The "OK" button is disabled until I enter something there. If I enter a space the rule doesn't match incoming e-mails with empty subject lines.

I also tried matching a specific header "Subject" "does not exist". That didn't work either. Maybe because the Subject line is included but is just the empty string.

Is there a way to achieve this?

Answer 1

You can do this by switching your thinking around a little to make Outlook look to see if the subject line is NOT blank.

Create a template for the message you want to send in reply. Then create a rule which will use the exception: "subject line contains specific words". You will add single letters into the exception criteria. Vowels work best because most subject lines are going to have them in it.

In essence, this rule will look to see if the subject line meets the criteria. If not (blank), it will reply with the template you choose.

Here are detailed instructions: Rule to AutoReply all correspondence without subject.