We have been having trouble receiving legit e-mails. So in attempts to correct this we have be tweeking some of the settings in the Admin GUI. Upon un-checking the " Hostname in greeting violates RFC (reject_invalid_hostname)" and saving, it seemed like it had not effect. Now when I try to re-enable the feature I get a error pop up that says...
and I cannot turn the feature back on. Has anyone seen this error before?