Resolve the ScanPST “Failed to Add Row to the FLT” Error: Full Guide

  Kumar Raj
Written By Kumar Raj
Anuraag Singh
Approved By Anuraag Singh
Modified On October 17th, 2025
Reading Time 5 Min Read

Though scanpst.exe or Inbox Repair Tool is not the best way to fix Outlook data file corruption, many users still use this for minor level of corruption. But, what if you get an error while fixing already corrupted PST file? This situation can only be compared to the moment when someone falls “out of the frying pan into the fire.”

One error that Inbox Repair Tool users often come across is “ScanPST Failed to Add Row to the FLT” Error. This is extremely annoying as it completely stops the process. If you are facing the same situation, this blog is for you. Here we will suggest some solution to this problem and also shed light on its causes.

What Happens When ScanPST Failed Issue Occurs?

Inbox repair Tool is an inbuilt utility that comes with MS Outlook. It is used to fix corruption but sometimes, it fall prey to different errors.

This error usually occurs when you start repairing a corrupt PST file. During the scanning process, scanpst.exe reports this error called “Failed to add row to FLT, RowID = nn in multiple times.

After reporting, a message, pops up that says, click Repair to fix the problem. Unfortunately, users do not see any Repair button at this stage. Hence, they fail to repair this error, let alone the corrupted PST / OST files.

What Causes ‘ScanPST Failed to Add Row to the FLT’ Error?

When ScanPST.exe is used to fix corrupted PST files, it may end up showing this error. Before going to the resolution of this problem, let us see what give rise to this error at the first place:

  • PST file over 20 GB: All PST files have a designated size depending on the Outlook version. Once the file size reaches the threshold or even crosses it, scanPST shows this error while fixing such files.
  • Dirty Shut Down / Outlook Crash: If you suddenly switch off your computer when Outlook is running or Outlook crashes, this problem may appear.
  • PST File Location: If the Outlook PST file is store in any Network location, this error might occur.
  • Virus Infection: When PST file corruption results from virus of malware infection, scanpst.exe may display this mentioned error.
  • HDD Issues: If there are some bad sector in your hard drive that damaged the PST file at the first place, then it might be reason you are getting this error.

Manual Ways to Resolve “ScanPST Failed to Add Row to FLT” Error

These are some free and manual workaround one may try when ScanPST Failed to Add Row to the FLT error occurs.

Workaround-1: How to Export Outlook PST file again for repairing.

Workaround-2: Make sure to safely close all other programs like Outlook or your antivirus software that might be using PST.

Workaround-3: One may also try transferring the PST file to a different computer and then use scanpst to repair it.

Workaround-4: Never use scanPST to repair PST file located in Network location. For repairing, make sure to copy it to a local computer.

Workaround-5: Remember that for larger than 2GB or which is encrypted the Inbox repair tool not responding error. If you have a large file you can divide PST file in smaller size and then repair it.

Fix ScanPST Failed to Add Row to the FLT” Error – The Expert Way

If you have attempted the mentioned manual tricks to avoid this error and still scanpst.exe shows you the same error, it is time to think smart. Do not waste your time fixing Outlook PST file corruption with Inbox Repair Tool and switch to SysTools PST File Repair Tool. This application is the best alternative to scanpst.exe and does not cause any error while fixing severe PST file corruptions.

Download Now Purchase Now

Additional Features of the Tool

Steps to Use the Automated Software

  • Step-1: Start the software on your computer.
  • Step-2: Click on Add File to add any number of PST file.
  • Step-3: Preview all items of PST file including the deleted ones.
  • Step-4: Export the recovered data in desired file format.

Frequently Asked Questions

Q. Why does the ScanPST report show the “Failed to Add Row to the FLT” error?
Because the Folder Lookup Table (FLT) has been corrupted or made unreadable. This may also occur when the PST file is too oversized to open, whether it is due to bad sectors, excessive size, or a crash of your system.

Q. Will ScanPST be able to repair a PST over 50 GB?
No. It is well documented that ScanPST will fail in that scenario. Therefore, we recommend that you use a dedicated tool such as the one shared above from SysTools.

Q. What does the “RowID” mean in the ScanPST log?
The Row ID describes the record or folder reference that could not be inserted into the FLT. Multiple RowID errors indicate corruption of the structure.

Q. How can I avoid ScanPST errors in the future?
Keep the PST file less than 20 GB, exit Outlook gracefully, do not store the PST on a network drive, and make periodic backups.

Conclusion

If you are facing “ScanPST Failed to Add Row to the FLT” Error while using scanPST for PST file corruption repair, you should stop using it immediately. Though there are manual methods to fix this error, these often does not work. You need professional software like the aforementioned utility. Follow the given guide and get done with such annoying errors.

  author

By Kumar Raj

A versatile writer with the vast knowledge of technology helps to reduce the gap between a user and technology. Provides easy and reliable ways to resolve multiple technical issues, which users encounter in their day-to-day life.