warum kann ich keine e-mails versenden? nicht 'mal an euch...

The original message was received at Fri, 15 Jul 2016 15:33:50 +0000

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hardware-team@cc.o2online.de

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(expanded from: hardware-team@cc.o2online.de)

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... while talking to localhost:

>>> DATA

<<< 550 5.7.1 u6FFXoJ9008954 This message does not comply with required standards.

554 5.0.0 Service unavailable