Can you provide more information so I can do the next step in troubleshooting.
- What did you do to get this error message? Can you provide a screenshot of the error?
- Is your environment on-premises, online, or hybrid?
- Did you have the issue when you moved your mailbox or folders?
- Is your device client or mobile?
- Is your account personal or school/work?
Based on past experience, it looks like your mailbox is being migrated or moved to a different server location, which could be the reason why you can't access it at the moment.
This can happen during IT maintenance, or when an organization upgrades or converts its email system.
Here are some steps you can take to try a preliminary solution:
- The migration process may take a while, wait for a while (the length depends on your environment) and then try to access your mailbox again.
- Try logging back in on a different device to see if the issue exists.
- If you have an IT department, please contact them to see if there are plans for the migration, or to see if there is an estimated time to receive an upgrade of downtime.
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