Spoof sent emails affecting use of account - Microsoft Community

as suffering spoofed emails result in 'delivery failed' messages in inbox, seem unable send account. email message got when sending old friend whom i've emailed hundreds of times reads:

'your message couldn't delivered because weren't recognized valid sender. common reason email address suspected of sending spam , it's no longer allowed send messages outside of organization. contact email admin assistance.'

since mine personal email account, don't have 'email admin'. advice welcome.

i should add that, having read other questions spoofed accounts, have changed account password.

it’s hard if compromised account or used address address, ndrs should stop within few days of them not using address. since changed password, shouldn’t using account directly, spoofing address. if so, knows how long address blocked. leaves new address best option.

can add new address outlook.com account set default - keeps old address on account new mail sent new alias - in 1 mailbox. people using old address still reach you. if blockage ever clears, can switch old address default.

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