If you're using an Exchange account that requires advanced settings, you'll need to remove the account and add it again using advanced settings. To add the account using advanced settings, see Add an account using advanced setup. If you have a Google, Yahoo! Mail, iCloud, IMAP, or POP3 account, check the settings in the advanced mailbox settings to make sure they're configured to your email provider's specification. If you're using an Outlook.com, Microsoft 365, or Exchange account, you won't have advanced mailbox settings unless the account was set up using advanced setup. If your problem is how quickly mail populates, change the download preference to headers then full items.

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From there, make sure that the proper calendars are selected. If none of these steps address the syncing problem, escalate the issue to the IT team. Third-party firewalls or antivirus software might prevent you from syncing your email and calendar events.

Turn off Windows Defender Security Center

If it is lower than 50 GB, you may have too many sync issues in which case you must delete the cache and re-run the sync, you can clear sync issues and test before deleting the cache. Some of the most common issues users encounter with Outlook Outlook repair with FixTechGuide on iOS relate to syncing. Learn how to troubleshoot when the iPhone Outlook app is not syncing. The approach that IT takes to address a syncing problem depends on what type of problem it is. If it's a client-side issue, the admin can usually instruct the user on what steps to take.

Check advanced mailbox settings

• These syncing problems usually happen because of issues like a damaged Outlook profile, poor internet connection, or a corrupted OST file.
• Check with your email provider for instructions about how to create an app password for your email account.
• For more information, see Add an account using advanced setup.
• In some cases, IT might be able to track down a problem by examining the Exchange logs.
• If two-factor authentication is turned on for your account, you'll need to create an app password for that account.
• If your password is incorrect, you'll see a message asking you to update your password.
• Online archive is only available online too, so no caching, hence it’s name.
• If you have a Google, Yahoo! Mail, iCloud, IMAP, or POP3 account, check the settings in the advanced mailbox settings to make sure they're configured to your email provider's specification.
• So, comments about his email box size aside (which I cannot change or make him clean up at this time), I need this fixed really fast today.
• For example, ActiveSync might not be enabled, or there might be a problem with the ActiveSync certificate settings.

Check the software documentation to learn how to temporarily turn it off. Firewalls and antivirus software might prevent you from syncing your email and calendar events. When issues occur at the account level, admins should ensure that users are properly logging into their accounts and provide them with instructions as needed. For example, admins might want to check the user's Exchange account settings and whether they can reach Exchange Server.

Check if two-factor authentication is turned on for your account

Windows Defender Security Center is free security software that's included with Windows 10. If you haven't installed alternative security software, you should temporarily turn off Windows Defender Security Center. We're sorry you're having problems with the Mail and Calendar apps for Windows 10. To fix the issue, please try each of the following solutions in order. Why not limit the caching to a more reasonable 1 year, if they need to access things outside of this, they can, they just have to click ‘view messages on server’ to do so. Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support.

Outlook calendar events or contacts not syncing

It’s best to cache what they need in an offline situation (for example, 1 year), then apply the archive to beyond this point. Online archive can take 24 hours or more to complete, it depends on what you have it set to archive. So, comments about his email box size aside (which I cannot change or make him clean up at this time), I need this fixed really fast today. Two-factor authentication helps protect your account by making it more difficult for someone else to sign in. It verifies your identity using your password and a contact method (also known as security info). While we all use systems differently, I don’t think I have 100GB of data after working for my company almost 25 years, let alone this much email.