How to Increase Outlook PST File Size Limit Easily

Many individuals export their mailboxes into PST files to back up or declutter their mailboxes. But once the PST file becomes oversized, the backup process may stop or fail. Therefore, one effective way is to increase Outlook PST file size. In this write-up, we will cover all the possible methods to increase the PST file size in Outlook. Keep reading this blog for a deeper understanding of how the process works. 

Why Is There a Need to Increase Maximum Size for PST Files?

The Outlook PST file stores mailbox data, is subject to a predefined size limit that varies by Outlook versions. Over time, as more emails, attachments, and other data are added, the file size can grow rapidly. When the PST file reaches its maximum limit, it can result in issues like:

• Outlook fails to add further emails or content
• MS Outlook may crash or behave unpredictably.
• Backup or archiving process may not complete or may fail.
• There’s a serious risk of files becoming corrupted or inaccessible. 

Increasing the PST file size will prevent such issues and keep Outlook efficient and error-free. 

Size Limit for Outlook Data Files

Given below is a table that shows the maximum Outlook PST File Size limit in different versions of Outlook. Take a look:

For Outlook 2016, 2013, 2010:

Name	Type	Valid Data Range	Default
MaxLargeFileSize	REG_DWORD	0x00000001 – 0x0000C800	0x0000C800 51,200 (50 GB)
WarnLargeFileSize	REG_DWORD	0x00000000 – 0x0000BE00	0x0000BE00 48,640 (47.5 GB)
MaxFileSize	REG_DWORD	0x001F4400 – 0x7C004400	0x7BB04400 2,075,149,312 (1.933 GB)
WarnFileSize	REG_DWORD	0x00042400 – 0x7C004400	0x74404400 1,950,368,768 (1.816 GB)

Manually Set PST File Size Limit via Registry Editor

In Microsoft Outlook 2002 and earlier versions, the default maximum PST File Size is 20 GB. And, in the latest versions like Outlook 2013, 2016, and 2019, the default maximum Outlook PST file size is 50 GB. 

This section explains how to increase the Outlook data file by using the Windows Registry Editor. MS Outlook supports four registry entries:

1. MaxFileSize: This sets the absolute maximum file size limit. The Outlook file can’t go beyond this. 
2. WarnFileSize: The size at which Outlook blocks adding new emails. Although the physical file size may still grow.
3. MaxLargeFileSize: It is used for UNICODE PST/OST files. This sets the maximum size limit they can reach. 
4. WarnLargeFileSize: This sets a warning limit for UNICODE PST/OST files before the file reaches its absolute maximum limit.

How to Use Registry Entries to Increase PST File Size in Outlook?

In this section, we will look at how to increase the size limit of the Outlook data file. The registry entries will differ according to the Outlook version being used.

Outlook Version	Policy location for registry entries in Registry Editor	User preference location for registry entries in Registry Editor
Outlook 2016	HKEY_CURRENT_USER\ Software\Policies\Microsoft\Office\ 16.0\Outlook\PST	HKEY_CURRENT_USER\Software\ Microsoft\Office\16.0\Outlook\PST
Outlook 2013	HKEY_CURRENT_USER\ Software\Policies\Microsoft\Office\ 15.0\Outlook\PST	HKEY_CURRENT_USER\Software\ Microsoft\Office\15.0\Outlook\PST
Outlook 2010	HKEY_CURRENT_USER\ Software\Policies\Microsoft\Office\ 14.0\Outlook\PST	HKEY_CURRENT_USER\Software\ Microsoft\Office\14.0\Outlook\PST
Outlook 2007	HKEY_CURRENT_USER\ Software\Policies\Microsoft\Office\ 12.0\Outlook\PST	HKEY_CURRENT_USER\Software\ Microsoft\Office\12.0\Outlook\PST
Outlook 2003	HKEY_CURRENT_USER\ Software\Policies\Microsoft\Office\ 11.0\Outlook\PST	HKEY_CURRENT_USER\Software\ Microsoft\Office\11.0\Outlook\PST

How to Manually Increase Outlook PST File Size?

By creating DWORD values – MaxLargeFileSize and WarnLargeFileSize, under the specific Outlook version, it is possible to increase the maximum size. This method also ensures reliability and improves performance while handling oversized PST files. 

The following are the steps to begin the process:

1. First, make sure to close the Outlook application completely.
2. Then, press Win+R, type: regit and hit Enter.
3. Now, go to: 

HKEY_CURRENT_USER\Software\Microsoft\Office\<version>\Outlook\PST

4. After that, navigate to Software > Policies > Microsoft > Office.

Now, replace the version with: 

Outlook 2016, 2019, 2021, MS 365	16.0
Outlook 2013	15.0
Outlook 2010	14.0
Outlook 2007	12.0
Outlook 2003	11.0

5. Then, right-click, click on New, and choose DWORD (32-bit) value.
6. Now, set the registry name as MaxLargeFileSize, right-click on it, and click on Modify.
7. Afterwards, choose Decimal under the Base section and enter the desired value in the Value Data section. Then, click on Ok.
8. Similarly, set the WarnLargeFileSize registry. 

Automated Way to Increase Outlook PST File Size

The Cigati PST Compress Tool is a reliable solution to reduce the file size of oversized PST files. The users have the option to compress either single or multiple PST files in one go. This makes it ideal for managing bulk data while ensuring data integrity. Moreover, it provides flexible options for handling attachments. Users can compress them, separate them from emails, or save them in their folder. 

1. First, download and run the tool.
2. Now, open it and Choose File Type as Microsoft Outlook (.pst).
3. Then, select from Single File or Multiple Files/Folder and click Next.
4. After that, click on Select File(s), browse, and open the PST/OST files.
5. Then, expand the tree structure and choose the folder that you wish to compress. Preview it and click Next.
6. Opt for the additional settings to refine the process.
7. Click on Path to Save to set the destination location. 
8. Finally, click on Start Compression to start the process.

Conclusion

The Outlook mailbox grows over the period of time and can eventually cause problems. Therefore, to prevent this, increase Outlook PST file size limit using the step-by-step instructions provided in this blog. Moreover, compressing the PST file size as soon as it reaches its maximum limit is a good option. For compressing the PST file, use the Cigati PST Compress Tool. The tool easily and quickly compresses the PST file size.

Frequently Asked Questions

Related Post