Attachment Librarian — Tutorial

You know the file exists. You know roughly who sent it. What you don't know is which of the nine emails has the current version. This indexes every attachment in your mail and groups them by document, newest first.

Tutorial — find the current version

Worked example: a scope of work that's been round the houses — you have Scope_of_Work.docx, Scope of Work v2.docx, scope-of-work-FINAL.docx and Scope of Work final (1).docx, spread across three threads and two senders.

1. Click Attachment Librarian in the Librarian ribbon group.
2. Set Days back — how far into your mail to index — and click Index my attachments.
You should see your attachments grouped into documents rather than listed as files. All four of those scope files collapse into one entry, with the versions stacked newest first.
3. Search to narrow — by file name, sender, or subject.
4. Click Open email on the version you want. You land on the message that carried it, in context, with whatever was said about it.
The index shows the newest 200 documents; search narrows further. That cap is there so a mailbox with fifteen years of attachments still opens instantly rather than grinding.

How it decides two files are the same document

It normalises the file name and strips the noise people add to versions:

StrippedExamples
Version tokensv2, rev, final, draft
Copy counters(1), (2)
Embedded dates2026-03-14, 031426
Separator differencesScope_of_Work = Scope-of-Work = Scope of Work

That last row matters more than it looks. Separators are normalised to spaces first — before anything else — because a word boundary doesn't fire next to an underscore, so Scope_of_Work_v2 would otherwise keep its v2 and split off as its own document. It's the kind of bug that produces a tidy-looking list that is quietly wrong.

Two files that should have grouped didn't? Someone renamed the document rather than versioned it — Scope of Work became SOW - District 4. Nothing can group those by name alone. Search by sender instead and you'll find both.

It only reads

Attachment Librarian holds a single, read-only permission (Mail.Read). It cannot send, delete, move, or modify anything — not your mail, not your files, not the attachments themselves. It builds an index and shows it to you. If it could do more, it would need permissions it deliberately never asks for.

Attachment contents are never downloaded while indexing — only the file names, senders and dates it needs to group things. There's no publisher server and no telemetry.