521 5.2.1 : (HVU:B1)

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hi can't send any mail to our customers since 14 jan , cause this error 521 5.2.1 : (HVU:B1)

ip reputation are neutral

we updated our system

and still the same problem

i tweeted this prblm on https://twitter.com/aolmailhelp but no one answer me

so if anyone have the same issue or have any idea about this

Comments

I am seeing the same issue. Have been trying to figure out since yesterday. No response from AOL till now.

Yes we have got the same error message yesterday.

mtaig-mbc02.mx.aol.com #521 5.2.1 : (HVU:B1)

There's a problem with the recipient's mailbox. Please try resending this message. If the problem continues, please contact your helpdesk.