If you have a large number of items in any single folder, you may experience performance issues during certain operations. For more information, see Outlook performance issues when there are too many items or folders in a cached mode .ost modern authentication troubleshooting or .pst file. To create a user profile, you must first create a user account. To determine whether this problem is caused by a corrupted user profile, create a user profile to see whether the problem still occurs when you use the new profile. To keep up with new viruses as they're created, antivirus software vendors periodically provide updates that you can download from the Internet.

Some Web-based Outlook add-ins don't work in when using on premise Exchange 2013

You can also add the secondary connected accounts (Gmail, flush DNS and re-sync Outlook Yahoo, etc.) in Outlook.com as additional accounts in the Outlook profile. Your user profile is a collection of settings that let you customize the computer appearance and performance. It contains settings for desktop backgrounds, screen savers, sound settings, and other features. User profiles help make sure that your personal preferences are used when you log on to Windows. As your mailbox size increases, more resources are required to open each folder.

Outlook Known issues in September 2024 updates

• Right-click the folder, and then click Properties to check your permissions for the folder.
• Although add-ins can enhance your user experience, they can occasionally interfere or conflict with Outlook.
• These steps are provided in a specific order based on commonality and complexity.
• The loading of unregistered MAPI services has been disabled by default to make Outlook more secure.
• If your antivirus software includes integration with Outlook, you may experience performance issues.
• Outlook forwards meeting invitations to other attendees without anyone actually sending an update or forwarding an invite.
• This occurs because custom form script is now disabled by default.

The loading of unregistered MAPI services has been disabled by default to make Outlook more secure. To edit a shared calendar, go online to your own Outlook.com calendar, open Calendar for Windows 10, or use a mobile device. Maybe you've added a new program to your computer that doesn't get along with Outlook, or your system has a virus. Regardless of the specific cause, there are several key troubleshooting fixes to try that might help.

Outlook known issues in the June 2018 updates

We're investigating the issues and will update this page when a fix is available. In the meantime, please use the workarounds suggested for each issue. If you typically use an Outlook.com account for email, this issue can occur if there are multiple aliases on the account and the 3rd party email address is the primary alias.

Outlook Known issues in November 2023 updates

For more information about when builds are available for their respective channels, go to Update history for Microsoft 365. We're investigating the issue and will update this page when a fix is available.



If your antivirus software isn't up-to-date, Outlook may not function correctly. Outlook stores certain data, such as email signatures and the spelling checker dictionary, in the AppData folder. If the network is performing slowly, Outlook must wait for read and write operations to the AppData directory to finish. To manage your mailbox by reducing the size of the Outlook data file, see Reduce the size of Outlook Data Files (.pst and .ost). Although add-ins can enhance your user experience, they can occasionally interfere or conflict with Outlook. There is currently no option to revert to the prior behavior, but we would love to hear your feedback to expert Outlook tips by FixTechGuide help us with future designs.

Step 2 - Make sure that Outlook isn't in use by another process

Occasionally, classic Outlook tries to run a process in the background. Auto-archive, sending and receiving a very large attachment, or running some of the other mailbox tools can all be done in the background. Check the status bar at the bottom of the screen to see if another process is running. If so, wait a short time (usually two or three minutes) to see if Outlook starts working again. If you can't choose any of the menu options, type inside an email message, calendar event, or contact, Outlook may have frozen. There are three steps you can take to try to get Outlook working again.

Outlook Known Issues in November 2021 updates

If you have email messages in an email program, you must import your email messages and addresses to the new user profile before you delete the old profile. If everything is working correctly, you can now delete the old profile. In System Configuration, if you select a check box, the related service or startup program runs when you restart the computer. If the check box is cleared, the service or startup program doesn't run when you restart the computer.