ScanPST Error Fix Guide When the Inbox Repair Tool Fails on Your PST File
The Inbox Repair Tool is the first medicine for a corrupt PST - but sometimes the medicine itself reports an error. This guide decodes each ScanPST failure and climbs the honest ladder beyond it.
By Technical AnshuOutlook 2010 to Microsoft 36510 minute read
The video shows this exact repair error being fixed live on a real corrupt PST
Your PST file is already corrupt, Outlook will not open it, and now even the repair tool has stopped with an error of its own. It feels like a dead end, but it is not: each ScanPST failure message points at a different cause, and most of them have a next step. The video above shows one real case fixed live. This guide covers the full family of ScanPST failures in the right order - protect the file first, decode the message second, repair third - so whichever error is on your screen, you know exactly where you stand.
Microsoft Outlook Inbox Repair Tool
An error has occurred which caused the scan to be stopped.
No changes have been made to the scanned file.
Scan progress before it stoppedPhase 4 of 8
Damage written to your file by this messageNone
What it usually meansSevere damage or interference
The scan stopped message is ScanPST protecting your file, not harming it - when this appears, nothing has been written to the PST.
1
Rule Zero - Work on a Copy, Never on Your Only PST
ScanPST does not repair in read-only mode. It rewrites the file in place, and anything it cannot understand, it discards. Running it on your only copy means a single bad pass can throw away mail the original file still held. Before anything else:
Close Outlook completely - check Task Manager that OUTLOOK.EXE is gone
Find the PST (Outlook shows the path under File, Account Settings, Data Files)
Copy the file in File Explorer and work only on the copy
Inside ScanPST, always tick Make backup of scanned file before repairing - it saves a .bak snapshot before every pass
There is a full guide to the copy-first routine in this series; treat it as non-negotiable, not as a tip.
2
Find ScanPST and Start the Scan the Clean Way
ScanPST is installed with Outlook but hidden. For Microsoft 365, Outlook 2021, 2019 and 2016 with the normal Click-to-Run install, it sits at C:\Program Files\Microsoft Office\root\Office16\SCANPST.EXE (use the Program Files (x86) version of the path if your Office is 32-bit). Older versions swap the folder: Office15 for Outlook 2013, Office14 for 2010, Office12 for 2007.
Double-click SCANPST.EXE and use Browse to select your copy of the PST
Click Start - the scan runs through 8 phases and reports what it found
Make sure nothing else is holding the file: Outlook closed, and ideally the file sitting on a local disk, not a network path
If the scan completes and offers a Repair button, take it - that is the happy path. The rest of this guide is for when it does not.
3
Read the Failure Before You Retry Anything
The message tells you which disease you have, and each one has a different cure:
Scan stopped, no changes made - the structure is badly damaged, or something interfered mid-scan (Outlook still running, an antivirus scanning the file, a failing disk)
Tool does not recognize the file or not a personal folders file - the header itself is destroyed, or the file is not really a PST at all
Fatal Error 80040818 - the classic signature of an old ANSI-format PST that has hit its 2 GB wall
Retrying blindly against the wrong diagnosis wastes the one thing you cannot recover - the file's remaining readable data. Decode first; the error-by-error breakdown has its own page in this series.
4
Run Repeat Passes the Way They Are Meant to Run
One pass rarely finishes a badly damaged PST, and this is documented behaviour, not a trick: ScanPST fixes the top layer of errors, which lets the next scan walk deeper into the file and find the next layer. The correct rhythm is:
Scan, note the error count, repair (backup box ticked)
Immediately scan the same working copy again
Keep going while the error count keeps falling - three to five passes on a genuinely damaged file is normal
Stop when a full scan reports no errors, or only minor inconsistencies
The warning sign is a count that stops changing: two identical results in a row means this tool has reached its limit on this file, and more passes only rewrite it for nothing.
5
Beyond ScanPST - the Honest Ladder
When ScanPST has done all it can, climb in this order:
Roll back one pass - if a repair made things worse, rename a copy of the .bak file to .pst and you are back to the pre-repair state
Import route - if the repaired file scans clean but Outlook still refuses it, create a fresh profile and a brand-new PST, then import the repaired file's folders into it
Extraction tools - paid third-party tools rebuild a new PST from the damaged one and often rescue items ScanPST dropped; judge them by a free preview, never by promises
Restore from backup - if you have one, it beats every repair ever written
One thing to set aside: raising the PST size ceiling with registry values is a different operation, covered in the PST size limit guide - and it is never the first move on a file that is already corrupt.
The honest line: no tool - free or paid - can promise 100 percent recovery from a severely corrupt PST. ScanPST discards items it cannot place, and some data in a badly damaged file is simply gone. Anyone who guarantees full recovery before even scanning your file is selling, not repairing. Demand a preview, keep your original untouched, and let the evidence decide.
Watch the Complete Process in the Video
The video walks through this repair error on a real file, step by step - watch it before you run your first pass.
ScanPST stopped with an error. Did it damage my PST further?
No. When the scan stops with that message, ScanPST writes nothing to the file - the message itself says no changes have been made. Risk starts only when a repair actually runs, which is exactly why every repair should run on a copy while the original stays untouched.
How many times should I run ScanPST on the same file?
Run scan and repair passes until one full scan reports no errors, or reports only minor inconsistencies. On genuinely damaged files that is commonly three to five passes. If two passes in a row report the identical error count with no change, the tool has reached its limit on that file.
ScanPST cannot recognize my file at all. Is the mail gone?
Not necessarily. That message means the file header or structure is too damaged for this tool - or the file is not really a PST. Check the file size (a 0 KB or tiny file holds no mail), confirm the extension, and then move to extraction-style tools or a backup; do not keep hammering a header-dead file with repeat scans.
This guide is based on the Technical Anshu video above - if a step gets stuck, ask in the video comments and you will get an answer there.