Skip to content

  • Projects
  • Groups
  • Snippets
  • Help
    • Loading...
    • Help
    • Submit feedback
    • Contribute to GitLab
  • Sign in / Register
T
troubleshooting-outlook-sync-problems6444
  • Project
    • Project
    • Details
    • Activity
    • Cycle Analytics
  • Issues 2
    • Issues 2
    • List
    • Board
    • Labels
    • Milestones
  • Merge Requests 0
    • Merge Requests 0
  • CI / CD
    • CI / CD
    • Pipelines
    • Jobs
    • Schedules
  • Wiki
    • Wiki
  • Snippets
    • Snippets
  • Members
    • Members
  • Collapse sidebar
  • Activity
  • Create a new issue
  • Jobs
  • Issue Boards
  • Charline Barkman
  • troubleshooting-outlook-sync-problems6444
  • Issues
  • #1

Closed
Open
Opened Nov 03, 2025 by Charline Barkman@charline07t362
  • Report abuse
  • New issue
Report abuse New issue

Desktop Old Outlook Not Syncing Recent All E-Mails 'Kinda' Urgent Email

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.

Additional Resources:

In the notification bar at the top of the app, select Fix account. If your password is incorrect, you'll see a message asking you to update your password. Before you begin, make sure that your device has the latest operating system and app updates. Try the general troubleshooting solutions in Troubleshooting Mail and Calendar apps for Windows 10. If that doesn't solve your issue, try the solutions below.

Desktop (Old) Outlook Not Syncing Recent / All E-Mails - 'Kinda' Urgent

How to force Outlook to sync manually?

In some cases, there might be outages or network-related issues, such as problems with a VPN. Mail flow issues can also arise out of other circumstances, such as a user having a mailbox in both Exchange Online and Exchange on-premises. In some cases, an issue might be related to MDM settings, such as restrictions on Outlook functionality, or user account and mailbox settings in Exchange. Sometimes an error appears in the Mail and Calendar apps when the apps try to sync new email or Troubleshooting Outlook sync problems calendar events. These syncing problems usually happen because of issues like a damaged Outlook profile, poor internet connection, or a corrupted OST file.

Want more options?

For example, admins might want to check the user's Exchange account settings and whether they can reach Exchange Server.Mail flow issues can also arise out of other circumstances, such as a user having a mailbox in both Exchange Online and Exchange on-premises.To fix the issue, please try each of the following solutions in order.Some of the most common issues users encounter with Outlook on iOS relate to syncing.On iPhones, it's also possible to sync calendars from mail apps such as Outlook and Gmail into the iOS Calendar app.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 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.Learn how to troubleshoot when the iPhone Outlook app is not syncing.

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.

Troubleshooting issues with iPhone Outlook not syncing

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.

How to Fix Outlook Sync Issues in Windows?

Change the limit to 1 year, wait for the sync, check the size of the OST once Outlook confirms all sync has been completed. Now change the slider to 2 years and follow the same principal. Outlook has a hard limit of 50GB per OST, decrease the period of e-mails that get cached, delete the cache, and re-run the sync.

Assignee
Assign to
None
Milestone
None
Assign milestone
Time tracking
None
Due date
None
0
Labels
None
Assign labels
  • View project labels
Reference: charline07t362/troubleshooting-outlook-sync-problems6444#1