Slow Outlook on Windows 11 is often fixed by updating Office, disabling problematic add-ins (File > Options > Add-ins), repairing your Office installation, creating a new Outlook profile, managing large mailbox sizes by archiving/deleting emails, or turning off Outlook's logging. Check your computer's resources, ensure Windows Search is indexed correctly, and if using the New Outlook, consider switching to Classic Outlook or managing cached mode settings for shared mailboxes.
Additionally, you can reduce performance issues by running Outlook in Cached Exchange Mode. In this mode, Windows Search or WDS searches the local copy of the mailbox instead of the mailbox content on the server.
Slow Outlook performance often stems from large PST/OST files or add-in conflicts. Start by disabling unnecessary add-ins via File > Options > Add-ins. Archive old emails to reduce mailbox size. Repair the Outlook data file using the Inbox Repair Tool (scanpst.exe). Ensure Outlook and Windows updates are installed.
How to Clear Cache in Outlook:
Slow application launch and delayed email loading after updates are common in New Outlook. After a Windows update, New Outlook may slow down due to compatibility issues or corrupted cache files. Start by clearing the Outlook cache and disabling unnecessary add-ins via File > Options > Add-ins.
10 Simple and New Ways to Speed Up Outlook
To scan Outlook for known issues and create a detailed report of your Outlook configuration, follow these steps: Select Advanced diagnostics, and then select Next. Select Outlook, and then select Next.
Thanks for checking before making changes, based on official Outlook for Mac guidance, resetting an IMAP account or clearing the Outlook cache removes only the local sync data for that account and then downloads mail again from the server. Emails stored on the mail server stay safe.
To clear your browser cache and cookies in Microsoft Edge, go to Settings > Privacy > Clear browsing data and select Ctrl+Shift+Del. You can also type "edge://settings/clearbrowserdata" in your address bar to access this function. Clear your browsing history, cookies, and cached images and files in minutes.
Cached Exchange Mode is designed to improve performance and provide offline access by storing a local copy of your mailbox. However, if you choose to disable this feature, Outlook will access your mailbox directly from the Exchange server without storing data locally.
Confirm that you're connected to the internet and check that connection including your wireless router and other equipment. You can also contact your internet service provider for any known outages in your area or to report a problem in your location. Organize your mailbox to make it faster in just a few clicks.
Repair an Outlook data file (. pst) file
Disable Add-ins: Sometimes, previously installed add-ins can interfere with Outlook's performance. Consider disabling any unnecessary add-ins. Reduce Mailbox Size: Large mailboxes can slow down performance. Try archiving old emails or deleting unnecessary items to reduce the size of your mailbox.
Follow these detailed steps to perform a thorough disk cleanup:
Clean up your inbox
Clearing the Outlook Cache
Clearing cache and cookies can be beneficial in certain situations. Cookies store information about your browsing habits and preferences, while the cache stores temporary data to improve website loading speed. Clearing them can help resolve issues like website errors or slow loading.
Clearing this cache and other temporary files can improve performance and keep things running optimally.
After clearing cache, you will have to sign back into any accounts that you were previously logged into.
The Conversation Clean Up feature in Outlook can reduce the number of messages in your mail folders. Redundant messages throughout a Conversation are moved to the Deleted Items folder.
Below, you will see some of the most common issues that users run into, and what the most efficient way to troubleshoot Outlook is.
Repair a profile in Outlook
To make Outlook look normal again, go to the View tab, click Layout, select Reading Pane, and choose "Show on the right" to restore the classic layout with email previews; alternatively, if you're in the "New Outlook," use the toggle in the top right to switch back to the Classic Outlook, or reset the view settings through View Settings > Reset View for a deeper fix, notes.