My outlook wont open

Start Classic Outlook in Safe Mode, close it once it finishes loading, and then reopen it normally; Microsoft specifically recommends this sequence when Outlook remains on Loading or Processing.^1^

1. Start Outlook in Safe Mode

1. If Outlook is still stuck, press Ctrl+Shift+Esc to open Task Manager.
2. Select Microsoft Outlook, then choose End task.
3. Press Windows key+R.
4. Enter:

      outlook.exe /safe
   

5. Select OK, accept the default profile if asked, and enter your password if prompted.
6. If Outlook opens, close it using File > Exit, then start Outlook normally.

2. If Safe Mode works but normal mode still hangs

An Outlook add-in is likely interfering with startup. Disable the add-ins without deleting them:^2^

1. While Outlook is open in Safe Mode, select File > Options > Add-ins.
2. At the bottom, set Manage to COM Add-ins, then select Go.
3. Take a screenshot of the selected add-ins so you can restore them later.
4. Clear all selected checkboxes and select OK. Do not choose Remove.
5. Exit Outlook and open it normally.
6. If it now works, enable the add-ins one at a time, restarting Outlook after each one. Leave the add-in that causes the hang disabled.

3. If Outlook will not open in Safe Mode

Create a separate Outlook profile rather than deleting the current one:

1. Close Outlook.
2. Open Start, type Control Panel, and open it.
3. Select User Accounts > Mail > Show Profiles.
4. Select Add, enter a new profile name, and complete the email-account setup.
5. Select Prompt for a profile to be used.
6. Start Outlook and choose the new profile.^1^

Do not remove the old profile yet. Removing a profile can also remove associated locally stored data files; first establish that the new profile works and that any needed data is backed up.^2^

4. Run the offered Microsoft diagnostic

The screen offering Run a Diagnostic is an appropriate next step if the preceding steps do not resolve the startup hang. On Windows 10 or later:

1. Select Run a Diagnostic on that screen; alternatively, open the Windows Get Help app.
2. Run the Classic Outlook startup troubleshooter.
3. Follow its recommendations and review the displayed results.

The troubleshooter must run on the same computer as Classic Outlook and does not apply to the new Outlook for Windows.^3^

Treat Check proxy and firewall as a separate connectivity suggestion, not proof that either one caused the startup hang. Run the startup diagnostic first; investigate the proxy or firewall only if the diagnostic reports a connectivity problem.

References

1. Classic Outlook not responding, stuck at "Processing," stopped working, or freezes | Microsoft Support
2. I can’t start Microsoft Outlook or receive the error “Cannot start Microsoft Outlook. Cannot open the Outlook Window” | Microsoft Support
3. Classic Outlook troubleshooters | Microsoft Support