Hi @Eric Leasner21 ,
What is the type of your mail account, POP, IMAP or Exchange?
If your have configured POP or IMAP account, you could make sure you have configured the correct port and Encryption. In general, the port for IMAP is 993, the port for POP is 995 and the port for SMTP setting is 465. (File>Account settings>Account settings>double-click the account>more settings>Advanced). For more details: POP, IMAP, and SMTP settings
If above configuration have configured correctly and the error still occurs, you could try to run outlook in safe mode to check if there are some add-ins cause this issue. (windows + R>type "Outlook.exe /safe">enter)
If all of above methods don't work for you, you could try to repair Outlook Data Files, the corrupted outlook date files also lead to this issue.
In addition, Improper MS Outlook installation can cause this issue as well, please try to reinstall outlook client and check again.
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