So, you can try repairing a PST data file with the Inbox Repair Tool first. That utility is located within the default C:\Program Files (x86)\Microsoft Office\root\Office folder. Outlook has an Inbox Repair Tool (otherwise SCANPST.EXE) that can fix corrupted PST data files. In which case, you’ll need to find a best PST file repair tool. If none of them work, however, then a PST fix might be required to resolve the issue. If you’re not sure, try some alternative resolutions to PST file repair first. However, there might be other potential resolutions for the issue. If Outlook displays an error message that doesn’t include a PST reference, you might need still need to repair a PST file. When Outlook displays an error message like one of the above, you almost certainly need to repair a PST data file to resolve the issue. The file xxxx.pst could not be accessed.”