Why is .pst compaction so agonizingly slow?

[Wowbagger]

It was brought to my attention that one of the users (Outlook 2003) has
~never~ cleaned out her .pst file which was now 7.6 Gb in size. Over the
course of a few hours I made several archive passes saving all of the 2004
emails into one .pst, 2005 into another and so on and now right clicking the
folder and selecting properties shows that the .pst file is less than half
of the original size.

(A separate question - why does archiving take so long? But that is for
another thread.)

Within Outlook the folder indicates that its size is 3.1 Gb, but within
windows explorer the file is still 7.x Gb in size. I set the compression
task to run, but after 5 hours the actual file size on disk has decreased
only by a few hundred Mb.

Why does the file compaction take so long? Is there a way - perhaps via
external utility - that will make it go any faster? This is a reasonably
modern machine with 1/2 Gb RAM. Why is Outlook spending so much time with
so little to show for it?

 

[Milly Staples [MVP - Outlook]]

Because removing 3 gigs of white space takes time.

--
Milly Staples [MVP - Outlook]

Post all replies to the group to keep the discussion intact. All
unsolicited mail sent to my personal account will be deleted without
reading.

After furious head scratching, Wowbagger asked:

| It was brought to my attention that one of the users (Outlook 2003)
| has ~never~ cleaned out her .pst file which was now 7.6 Gb in size.
| Over the course of a few hours I made several archive passes saving
| all of the 2004 emails into one .pst, 2005 into another and so on and
| now right clicking the folder and selecting properties shows that the
| .pst file is less than half of the original size.
|
| (A separate question - why does archiving take so long? But that is
| for another thread.)
|
| Within Outlook the folder indicates that its size is 3.1 Gb, but
| within windows explorer the file is still 7.x Gb in size. I set the
| compression task to run, but after 5 hours the actual file size on
| disk has decreased only by a few hundred Mb.
|
| Why does the file compaction take so long? Is there a way - perhaps
| via external utility - that will make it go any faster? This is a
| reasonably modern machine with 1/2 Gb RAM. Why is Outlook spending
| so much time with so little to show for it?