@Central Medical Laboratory
Thank you for your time and patience throughout this issue.
I did some more research and based off the message you're seeing; I found a potential solution that might help point you in the right direction.
Can't send email - undeliverable bounce back saying email not valid:
- If you are an Outlook.com user, you'll have to reach out to our support team directly via: https://support.microsoft.com/en-us/contactus/
- If you'd like to get on a call, you can check their Global Customer Service Phone Numbers
- If you are an Office 365 for business user, you need to contact your IT Admin to get this resolved.
I've also added our office-outlook-itpro tag to this thread so their community can take a look into this as well.
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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@Central Medical Laboratory
I just wanted to check in and see if you had any other questions or if you were able to resolve this issue?
Hi @Central Medical Laboratory ,
For further troubleshooting, could you share NDR messages where there are some causes for this issue? (Please cover privacy information )
Does this issue only occur to a specific recipient or all recipients when you send mails?
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