Converting a PST archive to PDF exhibits
A .pst is an Outlook personal folders file: an entire mailbox — mail,
calendar, contacts, tasks, folder structure and all — in one Microsoft
database file. It is what Outlook’s own export produces, and it is what lands
on your desk when a client says they exported their email.
EML Exhibit does not read .pst files, and there is no committed date for
it. Saying so plainly is more useful than a waitlist. What follows is the
route that works today, and the point at which this stops being a
self-service job.
What is actually inside a PST
Not a folder of emails. A .pst is a single-file database holding the
structure of a mailbox: the folder tree, message bodies and attachments,
calendar items, contacts, tasks and notes, along with Outlook’s own indexes.
Items the user deleted may still be recoverable inside it. Some are encrypted
with Outlook’s own scheme; some are password protected.
That richness is why it is a good archive format and a poor input to a conversion pipeline. Reading one correctly means implementing a database format, and reading one incorrectly means silently missing messages — the failure mode you least want in a production.
The route that works today
Outlook opens .pst files natively, which makes Outlook the tool for the first
half of this job:
Mount it. Opening the archive as an Outlook data file exposes the folder tree without importing anything into the live mailbox. This matters: importing merges the archive into the user’s mail and makes the boundary between collected material and live mail hard to reconstruct later.
Search inside it. Outlook’s search covers the mounted archive. This is where the in-scope set gets defined — custodian, date range, agreed terms, whole threads.
Export what is in scope. Classic Outlook gives you .msg. Getting to
.eml means either the web-client route or a local format conversion; both are
covered in converting Outlook email and
converting MSG files.
Convert the .eml batch. Ordinary from here: batches of up to 100, PDF or
TIFF, matter prefix, date sort.
The question worth asking before any of this
Where did the .pst come from? If a custodian produced it themselves by
running Outlook’s export, then the custodian decided what was in it. That is a
self-collection, and its defensibility depends on the custodian’s judgement and
good faith — both of which opposing counsel is entitled to probe.
That is acceptable in a great many small matters and it is how a lot of litigation actually proceeds. It becomes a liability when the case is contentious, when spoliation is likely to be alleged, or when the custodian has an interest in what was collected. At that point the correct answer is a forensic collection with a documented method, not a better converter.
Where this pipeline fits
For the small-firm case — one or two custodians, a few hundred responsive messages, a cooperative client — the manual route above is proportionate and gets you court-ready exhibits the same afternoon. For anything past that, use it for the last mile: after a vendor or a collection tool has produced a defensible, culled set of individual messages, this is what turns them into paginated PDFs with the header block intact.
How to do it in EML Exhibit
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Open the PST in Outlook
In Outlook, use File then Open and Export then Open Outlook Data File and select the .pst. The archive mounts as a folder tree in the sidebar. Nothing is imported or merged into the live mailbox by mounting it.
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Find what is in scope
Use Outlook's search across the mounted archive to isolate the custodian, date range and terms that are actually responsive. Do this before exporting anything.
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Get the messages out as .eml
Classic Outlook saves messages as .msg rather than .eml, so either drag the in-scope messages to a mail account you can reach through Outlook on the web and download them there as .eml, or convert the .msg files with a local utility. Converting Outlook email covers both routes.
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Convert in batches
Drop up to 100 .eml files in at a time, choose PDF or TIFF, set a matter prefix and sort by email date.
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Retain the PST untouched
The archive is the collected native. Keep the original file unmodified and record where it came from, who produced it and when.
Will PST support be added?
It is on the roadmap behind .msg, which is the more frequently
requested of the two. There is no date. A .pst reader is a substantially
larger piece of work than a .msg reader — the format is a database with
folder hierarchies, deleted-item recovery and encryption modes, not a
single-message container — and shipping a half-correct one would be worse
than not shipping it.
Is a PST even the right thing to be working from?
Often not. A .pst handed over by a custodian is a self-collection, which
is a method opposing counsel can question: the custodian chose what to
export, and Outlook’s export can silently omit items. For a matter of any
size or contentiousness, a documented collection is worth the cost. For a
small matter with a cooperative custodian, it is usually accepted.
What if the PST is password protected?
Outlook will prompt for the password when the file is opened, and you
need it from the custodian. Password-protected .pst files use weak
protection and there are utilities that remove it, but doing so without
authority is a problem of a different kind. Ask for the password.
How large is too large for this workflow?
If the in-scope set after filtering is a few hundred messages, the manual route is fine. If it is thousands, or if there are multiple custodians, or if deduplication and threading matter, this is a vendor job. The handover point is not really the file size; it is whether anyone will ever have to defend how the set was chosen.
Can I just convert the whole archive?
You should not want to. A full mailbox includes privileged communications, the custodian’s personal correspondence and years of irrelevant material. Producing it wholesale is a privilege-waiver risk before it is a technical problem — see privilege log.