Fix 0x8004060C Outlook Message Store Reached Maximum Size

The Microsoft Outlook application error 0x8004060C appears when your OST Message Store has reached its maximum size of 50GB. This can occur even if you are on Exchange Plan 2 which gives you 99GB of mailbox storage. Its the limitation of the OST file itself.

This results in an error message appearing (see image below) when you try to send or receive email in Outlook but it fails to synchronize the mail items with the mailbox server.

In this article I cover a 8 different potential solutions to resolve the Outlook error 0x8004060C.

 

Step 1: Clean Your Outlook Mailbox

By cleaning your mailbox, you can create more space for new emails. As a result, Outlook may synchronize the mail items. The steps are as follows:

• Open Outlook, go to File > Info > Tools and select the Mailbox Cleanup option.
• In the Mailbox Cleanup window, click Find items larger than, and in the input field, enter or select the appropriate value.
• Then, click the Find button. The Outlook will find and list emails of size greater than the value selected by you.
• Select the listed emails (that you think are no longer required) and then delete them. This will create space in your mailbox…
• After this, try to send or receive emails and check if the 0x8004060C error is resolved.

 

Step 2: Compact OST File

Another way to reduce the local mailbox size is to compact the OST file. To do this, follow these steps:

• Open Outlook and navigate to File > Account Settings > Account Settings.
• Click on the Data Files tab.
• Choose the Outlook data file (.ost) associated with your email account and click the Settings option.
• Click the Compact Now button in the Outlook Data File window that opens.

Outlook will compact (compress) the OST file automatically. It will remove the white space from the OST file, thus reducing the OST file size.

 

Step 3: Archive Emails

Archiving emails can help you move your old emails to a separate PST file that can be accessed locally in Outlook. This can significantly reduce the mailbox size and fix the Outlook error 0x8004060C. The steps are as follows:

• In Outlook, navigate to File > Info > Cleanup Tools > Archive. In some Outlook clients, you need to go to File > Info > Tools > Clean up old items.
• From the Archive this folder and all subfolders option, choose the folders that you want to archive.
• Enter a date in the Archive items older than the field.
• Then, click Browse to choose a location for saving the archive file.
• Click OK. The Outlook will move all emails older than the selected date to a new PST file at the selected location.

 

Step 4: Check for Virus or Malware Infection

To ensure that virus or malware infections are not causing the error, perform a thorough scan of your system using the antivirus software installed on your computer. If you don’t have one, use the built-in Windows Defender or install a reliable antivirus tool to get rid of any virus or malware that may be conflicting or creating issues, leading to Outlook error 0x8004060C.

 

Step 5: Update Outlook Application

To avoid the error 0x8004060C and other issues in Outlook, it is recommended to update your Outlook to the latest version. Here’s how you can do it:

• Open Outlook and go to File > Office Account.
• Click on Update Options.
• From the dropdown menu, choose Update Now.

 

Step 6: Disable Outlook Add-ins

Sometimes, third-party add-ins, especially incompatible or faulty ones, can interfere with Outlook’s functionality and lead to the error 0x8004060c. To fix this, you can disable the add-ins. The steps are as follows:

• Press the Windows key + R, type Outlook.exe /safe, and press the Enter key or click OK.
• In Outlook safe mode, navigate to the File > Options > Add-Ins.
• Select COM add-ins and click on the Go button.
• Uncheck all the listed add-ins and click OK.
• Then, restart Outlook normally (not in safe mode).

If disabling the add-ins fixes the error, then enable them one-by-one to find and remove the faulty add-in.

 

Step 7: Rebuild Outlook Data File (OST)

You can also try creating a new OST file to resolve any issues within the file. Follow these steps:

• Close Outlook and press Windows + R.
• Type Control Panel and press the Enter key or click OK. This will open the Control Panel.
• Go to User Accounts > Mail (Microsoft Outlook) and click on Data Files.
• Select the Outlook (.OST) data file linked with your email account.
• Click Open File Location. Then, right-click the OST file and choose Rename.
• Edit the file name with the .bak extension to create a backup copy of the original OST file.
• Start Outlook to automatically create a new OST file.

The Outlook will synchronize and download all mail items from the server. Once the synchronization is finished, you should be able to send and receive new emails without encountering the Outlook error 0x8004060C.

 

Step 8: Create a New Profile

Follow the steps below to create and set up a new profile in Outlook:

• Close Outlook.
• Press Windows + R, type Control Panel, and hit the Enter key.
• Go to User Accounts > Mail > Show Profiles.
• Click Add and type a new profile name.
• Click OK. Continue to follow the onscreen instructions.
• Then, click Next > Finish
• Once the profile is created, make sure to set it to default. You may also choose “Prompt for a profile to be used.“
• Then click Apply > OK.

Close the Mail dialog box and launch Outlook. Select your new profile from the dropdown and click OK.

Conclusion

I welcome your thoughts, questions or suggestions on my article on how to resolve the Microsoft Outlook application error 0x8004060C.

You may support my work by sending me a tip using your Brave browser or by sending me a one time donation using your credit card.

Let me know if you found any errors within my article or if I may further assist you by answering any additional questions you may have.