Google apps mail are spammed

Question

We have been using google apps gmail service for over 2 years. From about 2 months our mails are getting spammed or not reachng our clients. Spam prevention we have already used:

DKIM key authentication TXT Record

Checked our mail spam score on http://www.mail-tester.com which is always above 9. Can anyone suggest some measures to stop mail spamming?

Answer 1

Since you've got 9 out of 10, you're probably on one blacklist.

Find out what spam filter software those clients use, and what 3rd party blacklists those use. That one blacklist might be the cause. Try to get the reports from your clients spamfilter.