https://support.microsoft.com/en-us/office/repair-outlook-data-files-pst...
Path to ScanPST.Exe
Mouse click on START button in lower left corner
Outlook 2007: C:\Program Files (x86)\Microsoft Office\Office12
Click on c: in first column
In Second Column:
Click on Program Files (x86)
Click on Microsoft Office
Click on Office12
Click on ScanPST - it highlights
Open SCANPST.EXE by doing:
Double Click on ScanPST
A window opens to Browse to ALL *.pst file to repair
Select the first file and REPAIR button
Repeat for all *.pst files