How to Resolve Outlook Error Code 0x8004060c: A Comprehensive Guide

Microsoft Outlook is an essential tool for professionals, offering a user-friendly interface and a suite of features designed to enhance productivity. Despite its advantages, users may encounter various issues, with one of the most common being error code 0x8004060c. This error typically arises during email exchange from an Exchange server and is often accompanied by messages like:

• “Task ‘Microsoft Exchange Server: Sending’ reported error (0x8004060c): The message store has exceeded its capacity.”
• “Task ‘Email Address – Sending and receiving’ reported error (0x8004060c): Unknown Error.”
• “Task ‘Microsoft Exchange Server – Receiving’ reported error (0x8004060c): Unknown Error (0x8004060c).”

Understanding the root causes and resolving this issue can help users regain access to their essential email functionalities.

Understanding Outlook Error Code 0x8004060c

Before diving into solutions, it’s vital to recognize what triggers this error. Common causes include:

• Corruption of OST files due to excessive file sizes.
• Technical issues within the Exchange Server.
• Network problems leading to synchronization issues.
• PST file size exceeding the maximum limit.

By grasping these potential issues, users can better address the underlying causes of the error.

How to Fix Outlook Error Code 0x8004060c Manually

Here are several manual methods to troubleshoot and resolve the error:

1. Resetting Registry Files

To increase Outlook’s message capacity, you may need to adjust the Windows registry settings. Here’s how:

1. Press Windows + R to open the Run dialog. Type regedit and hit Enter to launch the Registry Editor.
2. Navigate to the appropriate registry path based on your Outlook version:
   • For Outlook 2013:
     HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\PST
   • For Outlook 2010:
     HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\PST
   • For Outlook 2007:
     HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\PST
   • For Outlook 2003:
     HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\PST
3. If the PST key is missing, right-click the Outlook key, select New > Key, and name it PST.
4. Double-click the MaxLargeFileSize value and set a new decimal value (e.g., 20 GB for Outlook 2003/2007 and 50 GB for Outlook 2010/2013).
5. Adjust the WarnLargeFileSize value to be at least 95% of the MaxLargeFileSize value.
6. Close the Registry Editor and restart Outlook.

2. Compacting PST/OST Files

Reducing the size of your PST/OST files can also alleviate the error. To compact your files:

1. Open Outlook and navigate to File > Info > Account Settings.
2. Select your account and click More Settings > Advanced tab > Offline Folder File Settings.
3. Click Compact Now and wait for the process to complete.

3. Reproducing OST Files

If your OST files are corrupt, creating new ones can help:

1. Close Outlook.
2. Go to the Control Panel, select Mail, then click on Show Profiles.
3. Choose your profile, click Properties, then Email Accounts.
4. Uncheck Use Cached Exchange Mode and follow the prompts to disable it.
5. After confirming the changes, re-enable Use Cached Exchange Mode.
6. Restart Outlook, which will generate a new OST file.

4. Splitting Oversized Files

If your OST files are too large, splitting them can help:

1. Launch Scanost.exe from its default location (usually in the Microsoft Office program files).
2. Open the truncated OST file to check its integrity.
3. If issues persist, consider archiving old emails to free up space.

Final Thoughts

Encountering error code 0x8004060c can be frustrating, but with these manual solutions, you can effectively resolve the issue. If these methods don’t yield results, you may want to consider using third-party tools like the Softmagnat OST to PST Converter Tool for more severe corruption cases. These tools often offer trial versions, allowing users to test their effectiveness before making a purchase.

With these steps, you can restore Outlook’s functionality and ensure your emails are flowing smoothly again.

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FAQs

1. What is Outlook error code 0x8004060c?
   • It indicates that the message store has exceeded its capacity, preventing the sending or receiving of emails.
2. How can I increase my Outlook mailbox capacity?
   • You can modify the Windows registry settings to increase the maximum size limit for your PST files.
3. What should I do if compacting files doesn’t work?
   • Try creating new OST files or archiving older emails to free up space.
4. Is there a reliable third-party tool to fix this issue?
   • Yes, tools like the OST to PST Converter can help resolve more severe corruption problems.
5. Can I prevent this error in the future?
   • Regularly compacting your PST files and managing email storage can help avoid reaching the size limit.