Mailbox RescueHow to open a PST file without Outlook
To open a PST file without Outlook, use a standalone PST reader. Mailbox Rescue opens the file on your PC, shows every folder and message, and can export everything to EML or MBOX. Outlook and a Microsoft 365 subscription are not needed.
Steps
- Download Mailbox Rescue (free) and start it.
- Drag your .pst file onto the window, or click Open file.
- Pick a folder on the left (Inbox, Sent Items or your own folders) and click a message to read it.
- To keep everything, click Export and choose EML, MBOX, a spreadsheet index or attachment files.
Why won't my PST open?
- Outlook isn't installed, or you moved to a new PC or to a Mac or Chromebook.
- New Outlook for Windows can only open PST files if classic Outlook is also installed and you have a Microsoft 365 subscription (details).
- The file is in use: close Outlook, or copy the PST and open the copy.
Is it safe to use an online PST viewer?
Online viewers need you to upload the whole mailbox to someone else's server. Mailbox Rescue reads the file locally and never uploads it.
Windows 10 and 11, Intel/AMD and ARM. No account needed. Works offline.
Frequently asked questions
Do I need Outlook or a Microsoft 365 subscription?
No. Mailbox Rescue reads PST, OST and MSG files directly. Outlook does not need to be installed, and no Microsoft account or subscription is needed.
Is my mailbox uploaded anywhere?
No. Everything happens on your PC. The only thing the app ever sends over the internet is your licence key when you unlock the full version.
What does the free version do?
It opens, searches and shows every message, and saves single attachments, without limits. Bulk export stops after 25 messages so you can check the result before you buy.
Is it a subscription?
No. The full version is $9.99 once and works on up to 3 PCs.
Updated 2026-11-08