Regardless of their mailbox size, Microsoft set a default OST size for a reason, while it can be changed, that doesn’t mean it should. If your password isn't the problem, you might have a certificate error. If so, you'll see a message that says, "There is a problem with the server's security certificate. The security certificate is not from a trusted certifying authority." Check with your email provider for instructions about how to create an app password for your email account.

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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.

Your account settings are out of date

Why is Outlook 365 getting emails on my phone but not my computer?

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 Fix Office 365 password reset problems 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.

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These syncing problems usually happen because of issues like a damaged Outlook profile, poor internet connection, or a corrupted OST file.For more information, see Add an account using advanced setup.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.

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

IT teams should build a plan to tackle these threats and make sure users are aware of the security concerns. If none of these steps work, the issue might be on the server side, which can make the troubleshooting process more complex. Admins must think about the nature of the problem and which users it's affecting to find the source. For example, ActiveSync might not be enabled, or there might be a problem with the ActiveSync certificate settings. In some cases, IT might be able to track down a problem by examining the Exchange logs.

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.