Error messages in Microsoft To Do

This may be due to your network connection. Using a VPN, proxy, or firewall could cause sync issues with To Do. Contact your IT admin to have these URLs approved:

• .microsoft.com

• .msecnd.net

• .live.com

• graph.windows.net

• graph.microsoft.com

• .office.com

• .office.net

• .office365.com

• static2.sharepointonline.com

• todo-web-endpoint.azureedge.net

• .microsoftonline.com

• .microsoft.io

• .windows.net

• microsoft-my.sharepoint.com

• microsoft.sharepoint.com

• login.microsoftonline.com

Make sure your IT admin also turns on these ports:

• 443

• 80

• 587

If you're trying to sign in to Microsoft To Do on the web and see a 503 error, this could be related to limitations in the local network or restrictions on a corporate network.

Check with your IT admin to make sure none of these URLs are blocked:

• .microsoft.com

• .msecnd.net

• .live.com

• graph.windows.net

• graph.microsoft.com

• .office.com

• .office.net

• .office365.com

• static2.sharepointonline.com

• todo-web-endpoint.azureedge.net

• .microsoftonline.com

• .microsoft.io

• .windows.net

• microsoft-my.sharepoint.com

• microsoft.sharepoint.com

• login.microsoftonline.com

Please follow the steps mentioned below to fix the error: 

Mac users: 

1. Uninstall the To Do app

2. Open Finder

3. Press CMD+Shift+G and enter ~/Library/Group Containers/UBF8T346G9.com.microsoft.to-do-mac/AccountData/userdatabase.db

4. Delete this file

5. Download the To Do app from the App Store again

iOS users:  

Reinstall the To Do app from the App Store