What is a PST file, and why does it need its own step?
A PST file is an Outlook data file stored on a computer or file share, outside the mail server, so server-based migration tools never see it. Outlook uses PST files for archives, for old mail people moved off the server to save space, and for exports. They are easy to forget, and they often hold years of important mail.
That is why PST archives are a standard part of our Exchange Server step-by-step guide and of the wider email migration guide. If you skip them, people discover missing mail weeks after the switch.
How do you find all the PST files?
You find PST files by searching computers and file shares for the .pst file extension and by asking people directly. Device management tools can search many computers at once. Without them, you will need to check each machine.
Look in these places:
- Each user's computer, including old archive folders Outlook created years ago.
- Network file shares and home folders.
- External drives and USB sticks people use for backup.
- Computers of people who have left, if they are still around.
Ask users too. A short note explaining why you need their archives works better than a surprise search. Our employee communication plan guide has tips for timing these messages. Record each file's owner, size, location, and whether it has a password.
How do you import PST files into Gmail?
You import PST files by running an import tool that reads each file and uploads its contents into a Google Workspace mailbox. Google offers Windows tools that import Outlook data, including PST files, into a Google Workspace account. Third-party migration services can also import PST files in bulk.
A reliable process looks like this:
- Copy the PST file to the computer running the import, rather than importing over the network.
- Close Outlook so the file is not in use.
- Import into the correct user's Google Workspace account.
- Check that the folders and a sample of messages arrived.
- Mark the file as done on your tracking list.
Imported folders become Gmail labels. Many teams keep archives under a clear label so old mail stays separate from current mail.
What if a PST file is damaged or password protected?
A damaged or password-protected PST file needs to be fixed before import, or the import may fail partway through. For a password-protected file, get the password from the owner and remove the protection in Outlook first. For a damaged file, Microsoft's Inbox Repair Tool, which comes with Outlook, can often fix the problem. Always work on a copy, never the only version.
Very large PST files import slowly. Start them early or run them overnight, and keep the computer from going to sleep.
Should you import every PST file?
No, not always. Before importing, think about storage, retention, and duplicates. Google Workspace storage is pooled across your users: 30 GB per user on Business Starter, 2 TB per user on Business Standard, and 5 TB per user on Business Plus. Large archives on Business Starter can use up space quickly. Our comparison of Business Starter vs Business Standard helps if storage is a concern.
Retention matters too. Once archives are in Gmail, they fall under any retention rules you set. If you use Google Vault, read our guide to Vault retention and eDiscovery. Finally, look for duplicates. The same archive is often copied to several places, and importing it twice clutters the mailbox.
Next step
PST collection and import can be included in our Exchange migration service. We track every file so you know exactly what moved.
Frequently asked questions
Can users import their own PST files?
They can, with Google's import tools and some guidance, but it is easy to import into the wrong account or skip damaged files. For more than a few users, a central process with a tracking list gives you a clear record of what moved and what did not.
Will imported PST mail be searchable in Gmail?
Yes. Once imported, archived messages sit in Gmail with the rest of the mailbox and appear in normal search results. Keeping them under a clear label lets people filter old mail in or out of a search.
