How does it work?

Just drag-and-drop PST and OST files onto the page. The Analyzer will scan them for issues, and provide a report

  • No signup or account required
  • It runs locally on your computer but using your web browser. Which means
    • You don’t have to download or install anything
    • None of your data is uploaded, guaranteeing privacy
      (test this by opening the Analyzer then disconnecting from the internet before selecting the file to scan)

Why is this useful?

  • You can validate your files for errors as soon as you receive them and without having to wait for them to upload to your eDiscovery platform
  • It runs blazingly fast - an estimated 5x faster than Microsoft's SCANPST tool! As a reference point, you can validate a 20 GB PST file in about 4-5 minutes (note: scanning is faster for files on solid-state drives than traditional hard disk drives)
  • Get a detailed report of issues and other details of your PST/OSTs

What exactly does it look for and report?

Here’s a sample report


This contains information about the file’s encoding and encryption, the number of files it is supposed to contain, and the expected file size. A mismatch between this and the actual file size or the contained files (scanned in subsequent steps) can indicate missing data

Block info

Blocks are a unit of data storage, and the PST contains a “Block Btree” structure that keeps track of these blocks. If any of these blocks cannot be located or there is a mismatch, it can make the stored data unretrievable. This can also be caused because of a truncation of the file during transfer where a file is incompletely transferred

Node info

The "Node Block Tree" (NBT) is a data structure in PSTs that acts similarly to a table of contents, specifying where all the emails and items are located within the PST file. When items are referenced in the NBT but cannot be found in the PST, this leads to errors. This often indicates that the PST is corrupt or that an update/write operation using the PST was interrupted

Subnode levels

There are many items that are carried within emails, such as attachments. These are separately scanned and verified

Folder tree

The folder hierarchy of the PST is validated. An issue here can lead to data being incorrectly read or inaccessible


The files are individually checked and cross-verified against the NBT and BBT

Data block integrity

Each block of data is scanned to ensure that there is no corruption of data. Checksum errors are identified at this point; these are caused by data failures in specific parts of the PST or specific attachments, possibly caused by an interruption during updating/copying. This kind of corruption may not be apparent in Outlook unless those particular attachments are directly accessed

Next Steps

If you’re dealing with PST and OST files, there’s more you can do to streamline your eDiscovery

Securely view PST and OST files using GoldFynch’s PST Viewer

If you want to view the emails and files your PSTs and OSTs contain, use GoldFynch’s PST Viewer. Similar to the PST Analyzer, it is a free, standalone browser-based tool that doesn’t require an account and doesn’t upload any of your data.

  • No file and email metadata is changed when you view the files, unlike Outlook
  • View raw file metadata such as MAPI properties
  • Conveniently view thousands of emails and their properties in seconds

Want to do more with your PST and OSTs?

If you want to search, review and produce your PSTs and OSTs, sign up to GoldFynch - an affordable, easy-to-use collaborative eDiscovery platform that boasts a powerful search engine, document viewer, production tool, and much more.

  • Search, review, redact, tag (label), produce and share your files using its convenient interface
  • Pricing is transparent and available up-front, averaging less than $6/GB/month. Sign up for a free trial case here
  • Share your cases with unlimited collaborators for free