SBCGlobal error 550 which gets displayed on the email screen constitutes to the issue when you are not able to send the emails due to a wrong email recipient. There are a few ways by which you can get rid of this error, and they are written below

Make sure that you are entering the correct email address of the recipient. Check the spellings or any numerical error and if you are in doubt, then confirm it in person
If there is an authentication error and you need to configure the SMTP settings, you need not worry for as long as you are working with email clients such as Outlook or Live mail as the authentication will be done automatically.

There are different ways by which you can resolve this issue and know about the same, make sure that you take technical assistance by dialing SBCGlobal tollfree number.

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