Compacting Outlook 2003 PST File

[Xiud]

I use Outlook 2003. I recently compacted my Outlook Data PST file. I
permanently deleted a bunch of files from my Deleted Items folder before I
compacted. The size of the PST file before I compacted is 795 MB. After I
finished compacting the file, I went to Windows Explorer to look at the
properties of the PST file and found that the PST file shows a “Size†of 795
MB & “Size on disk†of 631 MB. When I use my NTI Backup program to back up
my Outlook file to my CD-RW, I notice that it backed up a PST file with
“Size†of 795 MB. I was hoping that my backup program would backup the new
smaller compacted PST file of 631 MB because my backup CD can only hold 700
MB of backup data.
My questions are as follows:
(1) Why does my Outlook PST data file (as well as other data files on my
computer) show a “Size†& “Size on disk†when I look into its “propertiesâ€
content?
(2) What is the difference between “Size†& “Size on disk†of my Outlook
data file?
(3) What is the benefit of me compacting the Outlook PST file for backup
purpose when the compaction does not seem to reduce the Outlook data file in
a useful way?

 

[Roady [MVP]]

You are mixing up compacting features here.

What you DID is;
-using the NTFS compacting
This is used for transparant compressing on a file system level. That is why
you now see a size and size on disk. When you move away from the NTFS format
to a CDFS format it gets decompressed again.

What you WANT is;
-actually compressing the file
This can be done by rightclicking the root of the folder in Outlook->
Properties-> button Advanced...-> button Compact Now...

--
Robert Sparnaaij [MVP-Outlook]
www.howto-outlook.com

Tips of the month:
-FREE tool; QuickMail. Create new Outlook items anywhere from within Windows
-Properly back-up and restore your Outlook data

-----
I use Outlook 2003. I recently compacted my Outlook Data PST file. I
permanently deleted a bunch of files from my Deleted Items folder before I
compacted. The size of the PST file before I compacted is 795 MB. After I
finished compacting the file, I went to Windows Explorer to look at the
properties of the PST file and found that the PST file shows a "Size" of 795
MB & "Size on disk" of 631 MB. When I use my NTI Backup program to back up
my Outlook file to my CD-RW, I notice that it backed up a PST file with
"Size" of 795 MB. I was hoping that my backup program would backup the new
smaller compacted PST file of 631 MB because my backup CD can only hold 700
MB of backup data.
My questions are as follows:
(1) Why does my Outlook PST data file (as well as other data files on my
computer) show a "Size" & "Size on disk" when I look into its "properties"
content?
(2) What is the difference between "Size" & "Size on disk" of my Outlook
data file?
(3) What is the benefit of me compacting the Outlook PST file for backup
purpose when the compaction does not seem to reduce the Outlook data file in
a useful way?

 

[Xiud]

Hi Roady,

Thank you for your advice. I do not fully understand your advice however.
I do not know what you mean that I did the NTFS Compaction instead of the
CDFS compaction. What “moves or steps†did I make in Outlook to achieve
“NTFS Compacting� Based on your advice, I did a CDFS compaction (which is
what I have always done) per your step-by-step instructions to an Outlook
data file I have on another computer and the following is the result. The
PST file had the following properties before I did CDFS compaction: Size 475
MB & Size on disk 475 MB. Right after compaction, I noticed that the PST
file’s size & size on disk has not changed until I right-hand click on the
PST file & click a box “Compress contents to save disk spaceâ€. Then the PST
file’s properties changed to the following: Size 442 MB & Size on disk 346
MB.

My questions are as follows:

What else could I do to make the “Size†& “Size on disk†numbers to be
closer in size?

Why is there a different number between “Size†& “Size on disk�

Am I correct that my back up CD will need to be large enough for the “Sizeâ€
amount and not just the “Size on disk†amount?