When using your Microsoft Outlook you accumulate quite a bit of data over time – all of your emails, calendars, and other items will be saved on your computer. When these Outlook items are saved onto your computer they will always be kept in Outlook Data Files. There are two types of Outlook Data Files—.pst and .ost files. The .pst data files are used when setting up POP3, IMAP, and any web-based email accounts. The .ost data files are used when you have an Exchange Account set up and would like to work offline. When using an Exchange Server account, all of your data is going to be stored on the server, but you can have Outlook keep a local copy of that on your computer.
So what happens when you want to search these files for older items? Here’s a guide to searching and repairing the Outlook Data Files.
Search .pst Files
Your .pst file will contain all the items you’ve archived from Outlook. To search archived .pst files, you need to retrieve the archived items and open them in Outlook. Just follow these steps to search .pst:
- Open Outlook and go to Home > New Items > More Items > Outlook Data File
- Select the file named Archive (or whatever name you gave the file when archiving it)
- In the Outlook Navigation panel, expand the archive file. You can click on the subfolders to see the content of the file.
- To search for an item in the archived .pst file, just use Instant Search.
If you’d like, you can also import all of the archived items back into your Outlook Inbox, but it isn’t really necessary and can slow your Outlook down considerably (there’s a reason you archived these items in the first place!).
Your .ost files are a little different as these data files are “only a cache” of the files on the Exchange Server — to be able to search them, configure Outlook to “Use Cached Exchange Mode”:
- Go to File > Account Settings > Account Settings
- In the E-Mail tab, select the Outlook account you’re using and click Change
- In the Change Account window, check the box next to Use Cached Exchange Mode
- Click Next, then Finish
This will create a local copy on your computer of the Exchange Server data. It will make your Outlook functions, like search, work a little faster. Please note that it will take a while to create this local copy.
Repairing the .pst file
If you suspect that your .pst file might be damaged in any way, you may need to repair the .pst file. To repair the .pst file you need to use the Repair tool. Here’s how to do that:
- Open C:\Program Files or C:\Program Files (x86) in File Explorer
- Type scanpst.exe in the search box
- Double click to run the application
- Your default .pst or .ost file should already be selected. If not: find your .pst file
- Click Start
This will run a few scans on the data file. When it finds damage or errors it will ask you to click the Repair button, before doing so—check off the box that says ‘Make Backup of Scanned File Before Repairing’. Once the repair is complete, you can reopen Outlook.
When it comes to the .ost file, once again different rules apply. It is not recommended to repair the .ost file; instead you should re-create the file. To re-create the .ost file you should follow these steps:
- Exit Outlook
- Go to Control Panel and click on Mail
- Inside the Mail Setup window, select Email Accounts
- Click on the tab that says Data Files, choose the exchange account you need to repair (if you hover your mouse over it, look for .ost at the end of the name)
- Click on Open File Location to open a File Explorer window that will show the data file.