Updated On - November 4, 2022 by Henry Bray |Reading Time: 4 minutes
The size limit is always a matter when you are dealing with large files. As a result, many times we get emails with large attachments and, as a result, our PST files become larger. However, it is a minor issue, but it creates more errors. As usual, when users start receiving errors due to the increase in the maximum size of PST files, they seek possible solutions. In this article, we will talk about how to increase the maximum size for PST-files and OST-files in Outlook. Keep reading
Before starting, let’s learn a little about the default size for PST and OST files in Outlook
Actually, there is a default or suggested maximum size for non-Unicode PST and OST files in all Outlook versions, which is 2 GB. But the maximum recommended size for Unicode PST and OST files is not specific to all versions of Outlook. It varies depending on the version.
Generally, the MS Outlook 97–2002 version has a file size restriction of 2 GB and produces non-Unicode (ANSI format) files. If you are using Outlook 2003 and 2007, you have a storage limit of 20 GB, and for Outlook 2010, 2013, 2016, and 2019, the maximum recommended size or storage limit is 50 GB.
How can a user in Outlook increase the maximum size for PST and OST files?
Because the default size for PST and OST files is restricted, users may want to increase the size. It is possible to do so using the Registry Editor, which allows you to increase the size up to about 4PB (which is almost 4096 TB), depending on the versions of Outlook.
But before going forward, we want to inform you that this process isn’t workable for the PST and OST files of the Outlook 97-2002 versions that use non-Unicode (ANSI format) files.
What to do in the Registry?
To increase the maximum size of PST and OST files in Outlook, simply make two simple registry changes (in the locations listed below). As the desired directory is not specific to all Outlook versions, we have mentioned multiple locations. Find your version and go to the location.
Microsoft Outlook 2003
Microsoft Outlook 2007
Microsoft Outlook 2010
Microsoft Outlook 2013
Microsoft Outlook 2016
After going to the location according to your Outlook version, you need to set two new DWORD values.
1. WarnLargeFileSize: [Note: Set it no higher than “4090445042” (decimal) or “f3cf3cf2” (hexadecimal)]
2. MaxLargeFileSize: [Note: Set it no higher than “4294967295” (decimal) or “ffffffff” (hexadecimal)]
Actually, the first number (WarnLargeFileSize) specifies how many megabytes (MB) a user can write to a pst-or ost-file before receiving an alert that the file is overflowing. You can see in the above picture, it is set to 95 GB.
The second parameter (MaxLargeFileSize) specifies how many megabytes (MB) the system may write to a pst or ost file. Because there is more written to a pst-file and an ost-file rather than user data, this difference must be at least 5%. In the above picture, it is set to 100 GB.
Use professional software to solve the large PST file size issue in Outlook?
Usually, if you have hit the size limit in Outlook, you will start getting errors like sending or receiving errors, PST file corruption, etc. In this regard, the best and easiest solution for you is to delete some unwanted items and instantly get more free space.
But when you are attempting to delete files, you realize that all the files are important to you and you can’t lose them. Besides, you don’t have any backup. In this situation, you can increase the maximum size for PST-files and OST-files (this manual process is described above) with the Registry Editor.
Through the Registry, you can effectively solve the issue, but because of its critical steps, many users seek professional solutions. Now the question is, is there any third-party software that can solve the large file issue in Outlook? The answer is yes.
We will talk about the Regain PST Splitter software. Actually, it can’t do any setup that automatically increases the file size limit in Outlook’s settings or do any miracle that enlarges Outlook’s volume. But it has the functionality that can split the large PST files into small ones. And in this way, the size limit for PST files can be maintained without making any changes to the settings.
Let’s see how the Regain PST Splitter software works step-by-step.
- Firstly, you need to install the program on your computer or laptop (it doesn’t matter what your OS is).
- Then select and pick the desired PST file that you want to split.
- As per your requirements, fill in the appropriate options in the software.
- Choose the destination location where you want to save the split files.
- Lastly, to finish the procedure, press Next.
Furthermore, you can use this program to divide a corrupt PST file without losing any data. It can split a password-protected Outlook PST file into manageable chunks.