How to Split Oversized Outlook PST Files into Smaller Files

Large Outlook PST files can become difficult to manage, especially when they contain years of emails, attachments, contacts, and calendar items. Oversized PST files can cause Outlook performance issues, slow folder access, or file-size limit errors. Splitting a PST file into smaller files makes it easier to manage, store, and access your mailbox data.

With EdbMails PST Recovery Tool, you can split oversized Outlook PST files into multiple smaller PST files based on your preferred file size. The software allows you to preview mailbox contents, select specific folders or the entire mailbox, and export the data into new PST files while preserving the original folder hierarchy and mailbox properties.

EdbMails creates new PST files without modifying the source file. Whether you need to split a large PST file or recover data from a damaged or inaccessible PST file, the software simplifies exporting mailbox data into smaller, manageable files.

Why Split Outlook PST Files?

You may need to split Outlook PST files when they approach the size limit for their format and Outlook version. When a PST file nears its limit, Outlook may show errors while saving new items or accessing existing mailbox data.

• Unicode PST files: Outlook 2003 and later versions use Unicode PST files. Outlook 2010 and later have a default size limit of 50 GB, while Outlook 2003 and 2007 have a default limit of 20 GB. Splitting oversized PST files keeps the newly exported files below the configured size limit.
• ANSI PST files: Outlook 2002 and earlier versions use ANSI PST files, which have a maximum size of approximately 2 GB. Files near this limit may stop accepting new items or become damaged. ANSI PST files remain subject to this limit unless their data is exported to the newer Unicode format.
• Large mailbox archives: PST files that contain years of emails and attachments can be difficult to transfer or import. Dividing the exported data into smaller PST files lets administrators transfer or import archives in stages.
• Storage and backup restrictions: Some backup systems, file systems, and transfer services limit the size of individual files. Splitting the PST output keeps each file within those limits without reducing the total amount of mailbox data.

Prerequisites to Split a PST File

Before you begin splitting a PST file, ensure that you have the following:

• EdbMails installed on a supported Windows computer.
• Microsoft Outlook (classic) installed with a configured Outlook profile for PST export.
• The Outlook PST file that you want to split.
• Sufficient free disk space to save the newly exported PST files.
• A backup copy of your original PST file.

Steps to Split a Large PST File Using EdbMails

Step 1: Download and Install EdbMails

• Download EdbMails and install the application on your Windows computer.
• Launch EdbMails and log in using your registered email address and password.
• Select 'Outlook PST Recovery and Migration' from the product list.
• Select 'PST to PST'.

• Use the default job name or create a new job and continue.

Step 2: Select the Source PST File

• Click 'Browse for PST file' and select the PST file you want to split.

• Click 'Browse' to select the destination folder where you want to save the newly created PST files.

• Click 'Next' to continue.

Step 3: Preview and Select the Mailbox Folders

• Expand the mailbox folders to preview emails, attachments, contacts, calendar items, tasks, and notes.

 Note: You can select the entire mailbox to split all its contents into smaller PST files or select specific folders to export only the required mailbox data.

• Click 'Next' to proceed with the export configuration.

Step 4: Configure the PST Split Size

• Click 'Settings', enable the 'Split PST file' option, specify the desired file size limit, and save the settings.

Step 5: Start Exporting the PST File into Smaller Files

• Click 'Start Export' to begin the PST export process.

• Once the export is complete, EdbMails displays a completion message. Click 'View Logs' to review the export report and verify the exported mailbox item counts.

Validate Split PST Output

After completing the PST splitting process, verify the newly created PST files to ensure that the required mailbox data has been exported correctly.

• Check the exported PST files: Open the destination folder and confirm that the smaller PST files have been created.
• Open the PST files in Outlook: Use File > Open & Export > Open Outlook Data File to open each PST file.
• Verify mailbox contents: Check that emails, attachments, contacts, calendars, and folder structures are accessible.
• Review the export logs: Use the 'View Logs' option in EdbMails to check the export status and exported item counts.
• Keep the original PST file: Retain the source PST file until you have verified the exported data.

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Additional resources:

• Outlook PST Repair and Recovery Guide
• PST to Office 365 Migration
• PST to Exchange Migration
• EdbMails - Free Tools