How to Split Large OST Files?

Read time: 6 minutes

Offline Storage Files or OST files store user mailbox information on a local machine when they are registered with Exchange Server or IMAP server through Microsoft Outlook. After Microsoft Outlook connects & find the Exchange server address for the first time, this file is automatically created. As soon as the file is created, it is synced with the email server, so the data is available online and offline even if the email server is unreachable.

OST files contain all the items in your mailbox, such as emails, contacts, notes, tasks, & more. When the size of the OST file increases, it will negatively impact Outlook performance.

Additionally, the user may lose access to their important data if the size of the OST file leads to corruption. This is the problem with large OST files that force users to split them. Users can either split the OST files manually or with a reliable OST file splitter.

More about OST File Format

PST (Personal Storage Table) and OST (Offline Storage Table) file formats store emails, contacts, and appointments. These files can be of two types:

• 32-bit ANSI Format
• 64-bit Unicode Format

Earlier versions of Outlook had a lower file size limit. But the recent versions of Outlook support large file sizes. So, size issues are relatively less in the recent versions of Outlook.

Following is a list of the most common issues users experience when the OST data file size exceeds its limit.

• The Outlook program performs poorly.
• Synchronization problems occur.
• There is a delay in sending and receiving emails.
• Occasionally, Outlook freezes or fails to respond.
• Outlook does not respond.

First of all, you will have to remove all Outlook add-ins from the Outlook email client on your system. By disabling add-ins, you can improve Microsoft Outlook’s performance when it comes to opening, processing tasks, sending & receiving emails. Then try the following methods to solve oversized OST file issues:

You can easily split the OST file & reduce the size via archiving the OST data. Once you archive the OST data, you can prevent the OST file size from exceeding the default file size limit.

1. Log in to the Outlook account.
2. Tap on the File menu and hit on Tools.
3. Now, go to the option Mailbox Cleanup.
4. You can click on AutoArchive to move old mailbox items to the archive folder. Users also have the option of deleting items that are not needed.

Archiving is a good option to reduce the size of the OST files.

Kernel for OST to PST Converter converts OST files to PST files of specific sizes. So, you can save large OST files in multiple PST files. It can save email data, attachments, contacts, and calendar data even from corrupted OST files. Furthermore, it supports all versions of Exchange/Outlook OST files.

Managing large PST files becomes easy with its splitting function, which lets you split PST files according to size – 1GB, 2GB, 3GB & more. Below, we will see how to use this tool and split OST files as easily as per your desired size requirements.

1. Install and open the tool.
2. To split OST files by size, click the Browse button. To add more than one OST file, tap the + button.

Note: Use the option Search if you cannot locate your OST file.

3. Now, you need to select your OST file and tap OK.
4. View and confirm your selected OST file and tap on Next.
5. During the process, click Next and view your OST file data.
6. Then, select the PST file as your output file type to convert OST to PST file and click Next.
7. You can even select the desired filters namely Date Range, Item Type, etc. and save specific items to the PST.
8. Next, you’ll see the Split Option. OST files can be split by size from 1 GB to 45 GB. Select the size within the drop-down menu.
   
9. Now, pick a destination for your file. Tap on Ok and Finish.
10. In a few seconds, the process of splitting the OST file by size will be completed.

Final Words

We have provided the best solutions and methods to split the OST files – manually or via the OST file splitter tool. With our stepwise instructions, you can easily split OST files within seconds. It is recommended to keep a reliable OST splitter tool on your system, it will make your process easier, better, and 100% reliable.