Hi @Ashley
Thank you for posting your question in the Microsoft Q&A forum.
To help narrow down the issue, could you check Outlook on the web and confirm whether your scheduled emails appear in the Outbox there, or if the behavior is the same?
Here are some steps you may try:
1.Restart outlook
Open Task Manager > Process tab, scroll down to outlook.exe > Click End Process.
2.Start Outlook in Safe Mode
-Close Outlook completely.
-Press Win + R, type: outlook.exe /safe > Press Enter.
If Outlook opens normally in Safe Mode, the issue is likely caused by an add-in.
Go to File > Options > Add-ins > COM Add-ins > Go > Disable all add-ins, then re-enable them one by one to identify the problematic add-in.
Reference: Open Outlook in safe mode - Microsoft Support.
3.Create a new Outlook profile:
Control Panel > Mail > Show Profiles > Add > create a new profile > add your account > set as default > restart Outlook.
Please know that while our initial response might not resolve the issue right away, your input is incredibly valuable. With a bit more detail, we’ll work together to find the best solution for you.
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