Common issues with Outlook

Here are several ways on how to fix Outlook sync issues:

Route 1: Restart Outlook by right-clicking on the icon in the taskbar and selecting "Close windows/s".

Route 2:

1. Select the "Send / Receive" tab.
2. Click on "Send/Receive All Folders" and "Update folder":

Route 3: Before going this route it might be a good idea to copy the Outbox messages as they will be deleted.

1. Click on the "File" tab.
2. Select "Account settings" twice:
3. In the "Email" tab select your email account and click on "Remove" and then add it again under "New..."
4. If you get a message saying that you need to create a "Data File" then select OK and go to the "Data File" tab:
5. Click on "Add..." and save the file, you can delete it later:
6. Now repeat step 3.

Here you can see how to fix sync issues in Outlook on MacOS:

Option 1: Select "Tools" and then "Sync"

Option 2:

1. Select "Tools" and then "Accounts"
2. In the bottom left there is a + and - button, on the right side of those buttons there is a three-dot or gear button that you press. Then select "Reset Account"

Option 3: It might be a good idea to copy the Outbox (unsent mail) messages since they will be deleted.

1. Under "Tools" and "Accounts" select the minus button to remove the account and then plus to add it back.

If Outlook won't open or if it is stuck on the splash screen then you can try the following, assuming that you have already tried restarting the app, closing it in "Task Manager" or restarting the computer:

Route 1:

1. Open the control panel. Search for and select Mail:
2. Click on "Email Accounts...":
3. In the "Email" tab select your email account and click on "Remove" and then add it again under "New...":
4. If you get a message saying that you need to create a "Data File" then select OK and go to the "Data File" tab:
5. Click on "Add..." and save the file, you can delete it later:
6. Now repeat step 3.

Route 2:

1. Close every Microsoft 365 app (Word, Excel, PowerPoint, Outlook etc.)
2. Open the start menu. Type "Add or remove programs" and select it:
3. Search for "Microsoft 365 apps for enterprise". Click on the three dots and select "Modify":
4. Select "Online Repair" and repair. Once the repair is done try reopening Outlook.

Route 3:

1. Close every Microsoft 365 app (Word, Excel, PowerPoint, Outlook etc.)
2. Open the start menu. Type "Add or remove programs" and select it:
3. Search for "Microsoft 365 apps for enterprise". Click on the three dots and select "Uninstall":
4. Now try reinstalling Microsoft 365 (Office).