Sometime over the weekend, RBL started blocking every external e-mail. Folks who sent us mail were getting it bounced back with a 550 error. Once I unchecked the box to use recommended RBL's, mail started flowing again - Sophos UTM 320.
What's going on with the recommended RBL's? Is there a way this could be site specific, or is it a result of a change from the service recommending RBL's?
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