How to Move Offline Outlook Data File (OST) Data

Summary: By default, the OST file is stored in the ‘AppData’ folder of the user profile. However, users can relocate their offline Outlook data file or OST from its default location. In this blog, we’ve discussed the methods to move OST file from an Exchange account to another drive (internal/external), network storage, or a new computer.

A popular query related to the OST file is ‘How can I move the OST file to another location.’ We also came across such queries,

1. Without starting Outlook, I moved the IMAP OST from C drive to D drive. I hoped Outlook would ask me where the file is. However, it creates a new one at the same location. How do I make Outlook use the new location?

2. I’m running out of disk space on my main drive and noticed that my OST file was really big. I know how to move PST files, but that method does not seem to apply to OST files. Please help!

If you also have similar queries, read this post!

OST file is an offline cached copy of mailbox data stored on an Exchange server or an IMAP mail server. Outlook creates the OST file when you configure the Outlook in Cached Exchange Mode. It is saved at a default location on the computer under the user profile folders.

Although you don’t usually require moving or relocating the OST file, you may come across situations that may push you to move Outlook Data File to another drive or location. Some common situations where you need to move Outlook OST file from its default location are as follows:

• The drive where OST file(s) is stored runs out of free disk space
• You need to move the OST file to a new computer

Also Read: How to Transfer Outlook Data to a New Computer?

But moving or relocating an OST file from its default location isn’t an easy task. Unlike PST files, moving OST files requires you to perform multiple operations and is much trickier than you may expect.

Methods to Move or Relocate Offline Outlook Data File (OST) to Another Drive or Computer

You can move the OST file in Outlook 2010, 2013, 2016, and 2019 by following ways:

• Use ForceOSTPath Registry Key
• Use Symbolic Link
• While Setting Up Outlook Account
• Export OST File Data to PST

But before you proceed and perform any operations, backup your current OST file. If something goes wrong, you can restore the mail items, such as emails, contacts, attachments, etc., from the backup OST file to PST using Stellar Converter for OST software. The software can help you quickly convert large or oversized OST files into single or multiple PST files while maintaining data integrity. Thus, it can help you move the mail items from the OST file to another Outlook profile or computer.

The software can also help you move an inaccessible or orphaned OST file by converting it to Outlook importable PST format with 100% integrity. It supports conversion of OST files created by Outlook 2019, 2016, 2013, 2010, and earlier versions.

Method 1: Use ForceOSTPath Registry Key

ForceOSTPath is a registry key that you use to relocate or move the OST file from its default location to another drive or network storage. This is one of the best ways to move OST files without causing much trouble. However, this requires you to reconfigure your Outlook account. Thus, ensure that all the changes stored in the local OST file are synchronized with the mailbox before proceeding.

Caution: Registry keys store vital information about the system, settings, and applications. Any incorrect modification or accidental deletion of the registry key during this procedure can lead to severe problems. Make sure to follow the steps correctly and back up the registry (File > Export via regedit) so that they can be restored if something goes wrong.

The steps are as follows:

• Back up your current OST file via Import/Export Wizard, remove your Outlook profile, and close MS Outlook.
• Press ‘Windows’ + ‘R’ keys, type regedit, and press the ‘Enter’ key or click ‘OK.’ This opens the Registry Editor window.

Figure 1 – Type Regedit in Run Window

• In the ‘Registry Editor’ window, navigate to the following path based on the Outlook version installed on your system.

For Outlook 2019 and 2016
HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook

For Outlook 2013
HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook

For Outlook 2010
HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook

For Outlook 2007
HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook

For Outlook 2003
HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook

• Once located, right-click on the Outlook > New and then select Expandable String Value.

Figure 2 – Select Expandable String Value

• Right-click on the ‘New Value #1’ and choose ‘Rename.’ Then rename the key. Right-click on the ForceOSTPath key and choose Modify….
• Now open File Explorer and navigate to the location where you want to move the Outlook OST file. Copy the path and then paste it in the ‘Value data’ field of ForceOSTPath. Finally, click ‘OK’ to save the changes.

Figure 3 – Enter OST File Location

• Now, exit the Registry Editor and restart your system.
• Open Microsoft Outlook and configure your Exchange or IMAP account. The Outlook will create a new OST file at the location you entered in the ForceOSTPath registry key.

Note: If you’re using an IMAP account in Outlook 2010 or earlier version, you need to create a ForcePSTPath registry key as those versions use PST file for caching IMAP data.

If you find missing mail items after synchronization, you can import the backup PST file into your Outlook account.

Method 2: Use Symbolic Link

Symbolic Link, also known as soft link or symlink, is used in Windows to point the file or folder stored at another location. Thus, a symbolic link can be created using the mklink command to move the OST file to another location. By creating a symbolic link to the default OST file path, you point the MS Outlook to this new OST file location.

The steps are as follows:

• Close Microsoft Outlook and then copy the OST file from its default location (%localappdata%\Microsoft\Outlook) to the new location where you want to store it.
• Now open Command Prompt as administrator.
• Execute following mklink command:

mklink “C:\Users\user\AppData\Local\Microsoft\Outlook\abc@xyz.com.ost” “E:\MyOSTDataFile\abc@xyz.com.ost”

This creates a symbolic link to move the OST file. A shortcut is created at the default OST file location (C:\Users\user\AppData\Local\Microsoft\Outlook\abc@xyz.com.ost) that redirects the Outlook to the new location (E:\MyOSTDataFile\abc@xyz.com.ost).

To revert or change symlink, delete the shortcut (symbolic link).

Method 3: While Setting Up Outlook Account

You may also move the OST file to a different location while setting up your Outlook account via Advanced Outlook data file settings. The steps are as follows:

Steps to move existing OST file to another location:

• Copy your current .ost file from its default path to a new location.
• Open Outlook and then navigate to File > Account Settings > Account Settings.

• Select and remove the current account in your Outlook profile.

• Click New and then enter your username and password. The Outlook will connect to the server and retrieve your account information.
• In the ‘Add Account’ window, click ‘Change account settings and then click Next.

• Click More Settings and then under the Advanced tab, click Outlook Data File Settings.
• Click Browse to select the .ost file that you copied earlier and click Open.

To create and move new OST file,

• Click ‘Browse,’ choose the desired location, and then enter the file name. Press ‘Enter’ to create a new OST file at your desired location.
• Restart the Outlook for changes to take effect.

Now Outlook will use this location to store the mailbox data in the OST file.

Limitations of the above methods

• Modifying the registry key is a complex and risky process. Incorrectly implementing a single step to set up the ForceOSTPath key for changing Outlook .ost file location can have serious implications.
• The methods can help you move the OST file to another location on an internal or external drive or network storage connected to the same system. However, these methods can’t move OST files to a new computer or another system.   
• These methods can’t fix the OST file issues and errors. Works only when your Outlook profile and OST file are in a healthy state. It won’t work if the OST file is inaccessible/orphaned or when the Outlook account is not working.
• Exporting specific mail items from OST file to PST using Outlook built-in ‘Import and Export Wizard’ can take considerable time.
• Data integrity may be at risk.

Method 4: Export OST File Data to PST

An Offline Outlook Data File (OST) can only be opened with the account that has created it and on the same machine that was used to create that account. So, if you want to move the OST file to a new computer or another system, you will first need to convert OST file data to PST.

Assuming that you can access your Outlook account and the OST file, you can try exporting OST data to PST using Outlook Import and Export Wizard. The detailed steps are as follows:

• Open Microsoft Outlook and navigate to File > Open & Export, and then click Import/Export.

• From Import and Export Wizard window, select Export to a File and click Next.

• When the Export to a File dialog box opens, select Outlook Data File (.pst) and click Next.

• Now select the mail account or specific mail items (such as Inbox, Calendar, etc.) you want to export to PST.

• Click ‘Browse’ to select a location where you wish to save the exported OST file backup as PST and choose any of the options provided. Click Finish.

• You may be prompted to enter a password for the PST file (this is an optional step). Click OK to finish.

Note: The ‘Import and Export Wizard’ won’t work if the OST file is inaccessible or if the Outlook profile is damaged or the account is inactive. However, you can easily convert inaccessible OST files to PST by using Stellar Converter for OST software. The software also works when the Outlook account is not working.

Read this: How to Convert OST to PST free using Stellar Converter for OST software?

Stellar Converter for OST is a powerful OST to PST converter software that can help you move OST files to a new computer with complete integrity and precision. It is highly recommended by Top Editors.

Here’s the detailed insight about the Stellar Converter for OST.

Bottom Line

Sometimes, you may need to move Offline Outlook data file (OST) data to another drive or location. While modifying the ForceOSTPath registry key can help relocate or move the .ost file to another drive, migrating the OST file to another computer requires exporting the OST file to PST with Outlook ‘Import & Export Wizard.’ The wizard is accessible when the Outlook profile and OST file are active. To move an inaccessible or orphaned OST file to another computer, you can use the professional Stellar Converter for OST software. The software converts all or specific OST file items to PST in a few clicks without losing mailbox data. It can also help move multiple OST files by converting them to corresponding PST files.

Check out what MVPs say about OST to PST Tool from Stellar.