I ran scanpst on a 19 GB Outlook 2007 file. It found errors, I clicked on backup and repair.

I realize that the repair process may take a long time.
Scanpst window is not responding - that doesn't surprise me.
I checked with Task Manager, and I have noticed the following:

Scanpst takes between 1 to 4%  of processor time
Pagefaults HAVE increased from 12850  to  21919   after watching for 5 or so minutes
Pagefaults Delta has remained at 0

I looked in the Outlook folder, and I see a full backup copy.
The log shows that errors were found, but the last entry only says something about repair having been started.
I don't see any temporary file.

Do these observations indicate that scan pst is running?

Thanks.

• Moved by Lanlan HuangMicrosoft contingent staff Friday, April 03, 2015 2:05 AM

It can "take forever" on a large pst file - give it at least a couple of hours. As long as you have the BAK file, you can open task manager and end the task then restart the process - don't let it make a backup copy unless you first rename the original backup as the original is the last known good backup. 

Simple steps, like guide how to use ScanPST and some more..

1. Quit the application
2. Scanpst.exe is a hidden file so make sure that the 'Show hidden files and folders' setting is enabled in the folder options
3. Click Start | Search, or Find and type 'Scanpst.exe' in the Searchbox
4. Double-click to open the file and browse to the location of your damaged archive.pst
5. Click 'Start' to start the recovery process
6. Try to open the file in question again. The corruption problem should not exist.

- Use third party software if this guide didn't help you Outlook Repair Toolbox http://www.pst.repairtoolbox.com/