Frequently Asked Questions

If you cannot find the answer to your question in this list, please do not hesitate to contact us at

General Questions

Our software runs on the following versions of Microsoft Windows:
  • Windows 11
  • Windows 10 (32-bit and 64-bit)
  • Windows 8 & 8.1 (32-bit and 64-bit)
  • Windows 7 Service Pack 1 or later (32-bit and 64-bit)
Other system requirements:
  • 250MB disk space
  • 1GB RAM
  • .NET Framework 4.7.2 or later

Yes. You can try PST Walker software before purchasing it. The trial offers full access to all features for an unlimited time, with limited functionality.

The End User License Agreement (EULA) is available here.

The Global Trade Export Compliance Information is available here.

Installation and Activation

Our downloads include a user-friendly installer that will guide you through the entire installation process, suitable for all users. We also provide a portable version for power users.

To activate the software, purchase a license, and you will receive a license key for activation.

If you've lost your license key, please check the purchase email sent to you after buying PST Walker Software. If you cannot find the email, please contact us with the name and email address used for the software purchase, and we will retrieve your license key.

To move your PST Walker Software license to a new computer:
  1. Deactivate your license on your current computer.
  2. Download and install software on the new computer
  3. Activate your license on your new computer using your license key.

Error Messages

If you have just closed Outlook, it may take some time before it fully closes. Outlook could be running internal processes on the PST/OST file, such as Auto-Compact, or it may be waiting for another utility to finish its process, such as an indexer utility (Windows Desktop Search, Google Desktop Search, etc.).

Outlook might appear closed, but something is hijacking the 'outlook.exe' process, which has a lock on the file. As long as that process is running, you won't be able to do anything with the PST/OST files. This is usually the result of a specific add-in you have installed or an application that relies on the 'outlook.exe' process, such as Skype, fax software, or having a mobile device connected to your PC. Outlook is still running even when all Outlook windows are closed.

The error occurs when you run the incorrect version of software on your system. For example, if you have a 32-bit version of Outlook on a 64-bit Windows system, you might have mistakenly run the 64-bit software version in an attempt to match the bitness of your Windows OS. However, the Windows OS bitness does not play a role here. We provide both 32-bit and 64-bit versions of the software because your Microsoft Outlook can be either 32-bit or 64-bit. To resolve this issue, ensure that you match the bitness of Outlook itself and not the Windows OS.

  1. Delete the contents of the following folder, and then attempt to restart the software:
  2. Follow the instructions in the article linked below to repair Microsoft .NET Framework:
  3. If you still cannot run the application, install the latest version of .NET Framework 4.8