Best Methods to Clear Outlook Cache & Improve Performance

What Is Outlook Cache?

Outlook cache is temporary data stored locally on your computer to improve application speed and offline access. Instead of downloading mailbox data repeatedly from the server, Outlook saves copies of emails, contacts, calendars, and attachments in cache files. These cached files help Outlook open faster and allow users to access mailbox data even without an internet connection.

Common signs that your Outlook cache needs to be cleared:

• Outlook takes a long time to open.
• Search results are outdated or show emails you already deleted.
• Autocomplete suggests wrong or old email addresses.
• Emails are not syncing properly with the server.
• Attachments refuse to open or fail to load.
• Also, Outlook crashes without any clear reason. Users facing similar issues can also read our guide on Microsoft Outlook Keeps Crashing for additional troubleshooting methods.

Will Clearing Outlook Cache Delete My Emails?

This is the most common concern, and the short answer is NO. Clearing the Outlook cache only removes temporary local files. Your actual emails, contacts, and calendar data live on the server (Microsoft Exchange or Microsoft 365). Once you clear the cache, Outlook simply re-downloads everything fresh from the server the next time it syncs.

Manual Method to Clear Outlook Cache

Before clearing the Outlook cache, make sure your mailbox is properly synced with the server. This process only removes temporary Outlook files and does not permanently delete your emails or attachments.

Steps to Clear Outlook Temporary Files in Windows:

1. Firstly, close Microsoft Outlook and Skype for Business completely before starting the process.
2. Press Windows + R to open the Run dialog box.
3. Type the following path and click OK: %LOCALAPPDATA%\Microsoft\Outlook\
4. Locate the OST file and rename or delete it. If the file is hidden, enable “Show Hidden Files” and “File Name Extensions” in Windows settings.
5. Delete all .xml and .nst files available inside the Outlook folder.
6. Open the RoamCache folder and remove all files stored inside it.
7. Now, open the HubAppFileCache folder and delete all temporary files.
8. Open the Offline Address Books folder and clear all cached files.
9. Then, open the 16 folder and remove all items stored there.
10. Restart Outlook. The application will automatically recreate fresh cache files and sync mailbox data again from the server.

Clear Microsoft Outlook Cache in New Outlook for Windows:

1. First, close Outlook completely before starting the process.
2. Now, press Windows + R together to open the Run dialog box.
3. Type the following command and press Enter: olk.exe –devtools
4. In the Developer Tools window, open the Network tab.
5. Right-click anywhere inside the Requests table.
6. Select Clear Browser Cache from the menu.
7. Restart Outlook to refresh cached data and improve application performance.

Clear Outlook Cache on Mac (New Outlook):

1. Start by opening Outlook on your Mac system.
2. Go to Tools > Accounts.
3. Select the affected Outlook account from the left panel.
4. Click the Gear icon available at the bottom.
5. Choose Reset Account from the list.
6. Restart Outlook. The application will automatically rebuild the local cache and sync mailbox data again.

Delete Outlook Cache on Mac (Legacy Outlook)

1. Again, open Outlook and locate the Exchange folder in the navigation pane.
2. Right-click or Ctrl+Click the Exchange folder.
3. Select Properties from the menu.
4. Open the General tab. Click Empty Cache.
5. Restart Outlook after clearing the cache. Outlook will automatically download fresh mailbox data from the Exchange server.

Professional Tool to Clear Outlook Cache & Fix Outlook Performance

Manual methods can fix basic Outlook cache issues, but they may not work properly if Outlook data files are corrupted. In such cases, the DRS Outlook PST Recovery Tool is a reliable solution. It helps repair damaged PST/OST files, recover mailbox data, and improve Outlook performance without data loss. The software supports emails, contacts, calendars, attachments, and other mailbox items. Additionally, users facing Outlook account settings out of date errors or severe Outlook performance issues can also use this tool for quick and hassle-free recovery.

Simple Steps to Use the DRS Outlook Recovery Tool

1. Download and install the DRS Outlook PST Repair Tool.
2. Click on Open to add your corrupted or damaged PST files.
3. Choose Recovery Modes and other options. Click OK.
4. Then, you can preview all your recovered PST/OST files.
5. Lastly, click Save and choose the Saving Formats from the list.

Tips to Reduce Outlook Cache Size and Prevent Slowdowns

• Reduce the offline mail storage period from Account Settings to keep the Outlook cache smaller.
• Archive old emails regularly to decrease mailbox size and improve Outlook performance.
• Keep Microsoft Outlook updated to avoid cache-related bugs and performance issues.
• Restart Outlook periodically to refresh temporary cache files.
• Moreover, check the OST file size regularly, as oversized Outlook cache files can slow the application significantly.

Conclusion

In this technical blog post, we explored the best methods to clear Outlook cache and improve Outlook performance. Manual methods help remove temporary cache files, fix slow Outlook issues, refresh mailbox synchronization, and resolve outdated search results. However, if Outlook data files become corrupted or performance issues continue, the DRS Outlook Recovery Tool provides a reliable solution to repair damaged PST/OST files and restore mailbox data safely. Regularly clearing Outlook cache also helps maintain better speed, stability, and smooth email synchronization.

Frequently Asked Questions