Helping people with computers... one answer at a time.

Outlook's file format changed from Outlook 2000 to Outlook 2003. Unfortunately upgrading your existing Outlook PST is not automatic, and not easy.

I keep bumping into the 2 gigabyte problem with my PST. While I know I should probably devise a way to keep my PST smaller in general, I understand the Outlook 2003's PST format doesn't have the same problems as the older formats. When I upgraded to Outlook 2003, shouldn't it have upgraded my file format? And how do I do it myself?

Apparently when you upgrade to Outlook 2003 it does not upgrade the format of your PST. Similarly many folks including myself make a habit of upgrading or installing Outlook with our "real" PST squirreled away for safety, only pointing Outlook at it when the installation or upgrade is complete.

Regardless of how you get there, how to upgrade your "primary" PST isn't at all obvious. In fact, it's a tad cumbersome.

Fortunately, it's not something you need to do often.

The only way to get an Outlook 2003-formatted PST is to have Outlook 2003 create it.

If you use multiple PST files, then for all PST's except your primary, you can simply create a new PST in Outlook 2003, copy the contents of the old PST into it, and close the old. Fairly simple, actually.

But your "primary" PST - which is the one that contains your default delivery inbox, calendar, contact list and more - is special.

When you create a new PST in Outlook 2003 it does not contain all the necessary folders to be your primary PST. And there's no easy way to switch over.

So here's the process I use. Although a little convoluted, it works and does a reasonably good job of preserving all the little settings that you might otherwise forget about along the way.

  • Backup your PST. You never know - something could go wrong.

  • Start Outlook and switch to "Folder" View

  • Create a new PST. Using Outlook 2003, we create a new PST in the new format.

    • In the File menu, click on New and then Outlook Data File.

    • Select "Office Outlook Personal Folders File (.pst)" as the type of storage.

    • Place it in the same folder on your hard disk as your primary PST.

    • Give it a reasonably descriptive Name: such as "Personal Folders (New)"

    • Select the Encryption you want (I typically choose "Compressible Encryption".)

  • Exit Outlook

  • "Swap" Filenames. Outside of Outlook, we swap the two PSTs.

    "The only way to get an Outlook 2003 formatted PST is to have Outlook 2003 create it."
    • Locate your old and new PST files on your hard disk. Remember that we created the new PST in the same folder as the old.

    • Note the file name of your old, primary PST. Write it down if you need to.

    • Rename your old PST file to a temporary name, like "old.pst".

    • Rename the new PST file to the name that the old PST used to have.

    • Rename the old PST file with its temporary name to the name that the new PST used to have before the preceding step.

  • Restart Outlook. It will come up with your new PST as the primary/default PST. It will also note that several of the "special" folders it needs are not present, and will create them.

  • Move your "non-special" folders. By non-special I mean those folders that perhaps you created and that have no special meaning to Outlook.

    In each case you can simply drag and drop each folder from your old PST to your new one. If it's a top-level folder, drop it on top of "Personal Folders (New)" or whatever you named your new PST within Outlook.

    Note that by default, folders are moved, not copied - which means that they'll be removed from the old PST after they've been placed in the new. You can avoid this and perform a true "copy" operation by holding down the Shift key when you drag and drop the folders.

  • Copy the contents of Special Folders.

    • Inbox: Outlook will have already created an inbox in your new PST. Copy the contents of your old inbox into the new. If you created sub-folders within your inbox, you'll need to copy each of those individually to your new inbox.

    • Sent items: Copy the contents to the Sent Items folder in your new PST, just like you did your Inbox.

    • Calendar: click on the calendar in your old PST. Then click on the View menu, Arrange By, Current View, and then click on List. Your calendar should now appear as a list. Select all, using CTRL+A, and now drag the calendar items from your old calendar list and drop them on the Calendar in the new PST.

    • Contacts: Much like you did with your calendar, click on your Contacts folder, select all with Ctrl+A, and then drag & drop the contact entries to the Contacts folder in your new PST.

  • Close the old PST. Right click on the old PST in the Folder View, and select Close.

Yes, it should be easier. I haven't yet tried Outlook 2007, but I hope it will be easier there. But for now, this should convert you to an Outlook 2003-formatted PST.

It did for me.

Article C2857 - November 30, 2006 « »

Share this article with your friends:

Share this article on Facebook Tweet this article Email a link to this article
Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

Lou Gascon
December 2, 2006 12:22 AM

Well now Leo, you naughty little Lion. I do like to come here and see your little tweaks and advice notes, and todayís newsletter certainly puts the Cat amongst the Pigeons for me...!

Based on the notes above, I gotta assume that I need to reformat my main PST files to keep them sylph like within office 2003...

My problem is, and before I do; I have 13 old PST files in addition to 3 main files called:
1] (Admin/outlook) Personal folders(1).pst
2] F:\Outlook\Personal Folders pst\Outlook.pst
3] F:\Outlook\Personal Folders pst\2.1.08Kb\outlook.pst
And two other files called:
4] F:\My Documents\My.Pst files\ MyPracticePst.pst
5] F:\My Documents\My Practice Files\ManagePST\ ManagePST.pst

I believe 1] to be the main file currently in use. And I think 2] and 3] were created as a result of a previous tweak done with you; Personal Folders: why am I seeing them listed more than once in Outlook? - 4] & 5] Iím not sure about...!

However, the other 13 are all old saved files that I had accidentally deleted (Donít ask!) and retrieved by using a variety of retrieval programs during March of this yearÖ

The problem is, I need to see what is in those 13 files and to place any required files into my main folder before I delete the old files...?

On my knees now: How can I read the old PST files...?


Leo Notenboom
December 7, 2006 5:50 PM

Any particular reason you can't just File->Open->Outlook datafile?

December 22, 2006 8:55 AM

Hi Leo, I have a when receiving plain text file in my Outlook 2003. I found the explaination in MS web site. It is because I am using the older 97-02 outlook data file format. But I found an slightly easier solution for transfering old data file to 2003 format.

After you created the new format, no need to exit and swap the file. Just try copying all the necessary folder in the OLD data file into the NEW data file, by right click on each of the folder and copy. (Some folder may not be able to copy)

Then goto Tool-Email Account-View&Change. Select the new data file in the "Deliver new e-mail to the following location:

Then exit outlook and restart. If the Junk Email folder is missing (My case), just try dragging the Old data file's Junk Email folder into the new one, then some error might occur, later the JunkEMail will be working again.

You may need to create a new Archive folder too and change the archive into the new folder to support UniCode.

December 22, 2006 8:56 AM

sorry, my previos post :
"Hi Leo, I have a when receiving plain text file in my Outlook 2003. " should be

Hi Leo, I have a problem when receiving plain text file in my Outlook 2003 (the email body is blank).

Greg Walter
January 30, 2007 6:40 AM

I just upgraded from Office XP to Office 2003. I installed 2003 over XP and went to implement your procedure for upgrading my Outlook.pst from XP format to 2003 format. When I try to create a new Outlook data file (File > New > Outlook Data File) the dialog box that comes up is empty -- I can't choose a "type of storage" or go any further. Any suggestions?

January 31, 2007 6:51 PM

I was using Office 2007 Beta before. But today it is expired.
I re-install my Office to 2003, but I could not open my Personal Folder that created by Office 2007 in Office 2003.
What should I do??

Leo Notenboom
January 31, 2007 11:22 PM

You'll need to get an Outlook 2007 in order to read that PST in the new format.

February 8, 2007 11:22 AM

Hi, Leo. This is my first time checking out your site, and it's great. Thanks very much for such a helpful service! I have two questions about your advice for porting into Outlook (Office) 2003 Pro: (1) When I did everything according to your directions (and they're much better than Microsoft's, so thank you!), I ended up with three .pst files -- (a) the default "Outlook.pst" file created when I first install Outlook 2003 and use the wizard to set up an email account; (b) the .pst file you suggest we create by going to File/New/Outlook Data File (In your example, we name this one "Personal Folders (New).pst"), and (c) our original .pst which I've been using for a couple of years (I call this "MyGoodData.pst."). When I exit Outlook and swap the names, the NEW data file I created (which had been called "Personal Folders (New).pst") is now called "MyGoodData.pst," and the file I've been using for years is renamed to be "Personal Folders (New).pst." So...what happens to "Outlook.pst," which is the default created by Outlook when I first install 2003 Pro? Question # 2 is: I can port over all of my data by using your instructions, *except* that my rules/alerts AND my email accounts are NOT imported, so is there a way to handle these? Again, thanks so very much!

Leo Notenboom
February 9, 2007 4:12 PM

Hash: SHA1

The original Outlook.pst - if it's something you've never actually used,
can be closed and ignored.

Rules are not stored in the PST. You can, in the rules dialog, export
them to a file, and then import them from a file.

I'm not aware of an easy way to migrate account settings. I've heard of
an add-on commercial (for $$) tool, but have never used one. I've always
retyped by hand when I've needed it.

Version: GnuPG v1.4.6 (MingW32)


Paul Baderman
April 16, 2007 7:30 AM

Hi Leo
Great tips - many thanks. Don't know why Microsoft in all their wisdom couldn't put such a helpful page together, or better still, release a free gizmo that does it all for you. Anyway, I am following through your steps and all is fine until I get to the Calendar section. There is no option anywhere to select List view. Without it, I can't drag and drop as you suggest. I'm stuck now. Help please ..? Thanks.

April 20, 2007 6:04 AM

Um, why not just close Outlook, rename and backup your existing PST, open Outlook (forcing it to create a new, empty PST in the current format), and then use File -> Import from your old PST? I found copying over each data folder to be an error prone process.

Karl Fisher
April 20, 2007 7:48 AM

I tried doing this with an IMAP account. It worked in 2007 except that now Outlook asks for my password three or four times a day even if I check the box to remember. In Outlook 2003 I couldn't get it to work, when I create a new IMAP account, it uses the old 97-2002 format, and if I try to rename it to a new format I created, it just doesn't work. Thoughts?

Gil Sudai
May 29, 2007 4:34 AM

This procedure does not work with Outlook 2003 and IMAP. When I create IMAP account it uses the old PST format. Renaming it (like suggested here) does not work. HELP!!!

Nathan Schultz
June 13, 2007 9:46 PM

Microsoft's suggested upgrade path to 2003/7 format:

July 24, 2007 3:55 AM

Hi, does anybody know how I downgrade a .pst file from outlook 2003 to 2002? I am switching computers the "old" has outlook 2003 and for the new I only have outlook 2002 availeble. Tx, Marco

September 5, 2007 7:15 AM

Leo, I tried this, but there's a problem. When I transfer my Outlook 2000 recurring all-day calendar items, once it gets into Outlook 2003, each all-day items now spans across 2 days, rather than being for one day. Any idea how to solve that?

September 7, 2007 2:25 AM

Is is possible to associate the extension .PST with outlook.exe 2003 or later such that when double-clicking on such a PST file from explorer(without encryption or password protection) that outlook opens the PST without having to use the "Data File Management" wizard ? Using explorer, a new message is opened and the PST is embedded in the email and can also not be opened by double-clicking on the file.

September 30, 2007 9:18 PM

Everything worked great, except for the calendar. I do not get "List " as an option (from View > Arrange By > Current View).

November 29, 2007 8:15 AM

The most easy way is to create a new Outlook data file in 2003 format, and then import all the data from the old PST file with Microsoft Outlook 2003. Outlook 2007 can also work in this way.

In case your file has already get into the 2 gb problem, then Outlook cannot help you. But you can still follow the way in to make the conversion and upgrade.

November 29, 2007 8:19 AM

Hi, Macro,

You can use Outlook 2003 to create a new data file in the old Outlook 97 format, and dump all the data from the Outlook 2003 format file.

You may also follow the instructions in , though such a downgrade requirement is rare.

Jo„o Carlos
February 24, 2008 12:32 AM

Thank you very much for this tip. Everything worked well except the fact that I get an error message when I try to bring contacts at the New Message dialogue. I click OK, the the contacts list shows empty. I have to pulldown the address book list on the top right corner and choose the second occurrence of "Contacts".

June 16, 2008 6:51 AM

Whenever I have trouble with PST files that weight more than 2GB I use this to fix it. It allows me to reduce the file size by splitting it up it several smaller files.

Sammy Samuels
June 24, 2008 10:59 PM

There is one more easy solution to upgrade Outlook to Outlook 2003 (Unicode). Download easy & quick SysTools PST Upgrade Tool to upgrade PST files of Outlook to Outlook 2003/2007.

Download the software from:

Effy Teva
October 15, 2008 2:55 PM

Too bad PST upgrade isn't free for home users !
Otherwise it might be useful ...

January 5, 2009 7:38 PM

Thanks for the tip! I would like to add one other tip - I use a handheld (HP IPAQ) - after doing what you suggested activesync no longer worked and told me that the outlook profile changed - the specific code was
"activesync support code 0x8503001F"
I needed to then go in and delete the partnership and recreate it.

Just a note I am working with outlook 2003 on Windows Vista.

thanks again..

February 6, 2009 7:43 AM

After an 18 hour power failure (while many programs were open)we have no email or contacts when we open Outlook 2000. We have an old pst file from last year. Is it possible to have lost the current pst file entirely?

Robert Ingenthron
June 15, 2009 4:57 PM

Great article and good comments, too.

If you are like me, getting about 500 emails per day and running at least 12 mailbox rules to sort email, one extra step that is helpful due to the time-consuming nature of this "upgrade" process is to stop the incoming mail flow until everything is ready to go.

In Outlook 2003, go to "Options", "Mail Setup", then click the "Send/Receive" option button. Form there, you can "Edit" the "All accounts" group. In there, you can either uncheck the "Receive email" checkbox, or uncheck the "Include in this group" option".

Or, if you don't like mucking with settings, simply pull the Ethernet cable until you are done. (If you are just copying from an old PST format to a new format, it won't matter if you are on an Exchange server.)

-- Rob "I" --

July 3, 2009 5:54 AM

Thanks for these posts. One obvious question that wasn't answered by this and related articles on this site, is whether the 2 GB pst repair problems affect 97 format PST, 2003 format PST, or both. I have Outlook 2003 with the old 97 format PST, and Outlook simply stops putting any more in the PST once it reaches 2 GB (eg. stops receiving email etc), thus preventing the file from growing larger than that. Which suggests problems with PST files > 2 GB might only be with 2003 format PSTs? But given all the comments, that's not at all clear, despite the fact that none of the 2 GB repair tool solutions mentioned say anything about 97 vs 2003 formats. In other words, I want to know whether by upgrading to the 2003 format, and of course quickly exceeding 2 GB, I'll now make my PST susceptible to not being repairable. If that's the case, the whole article's purpose is questionable, so I want to know :-) Can this be clarified?

Eran Livneh
October 25, 2009 10:24 AM

Very helpful instructions, thank you! One thing that did not work for me as described is the calendar folder. I could not find a List view in Outlook 2003. Instead, I used the Active Appointments view. You can also customize the view to inlcude appointments for any time range.

Eran Livneh
October 25, 2009 10:26 AM

And one more thing: don't forget the Tasks folder if you have any (it's one of the "speacial" folders so you would have to copy the tasks from the existing folder to the new one).

June 1, 2010 11:45 PM

ANSI PST Files has file size limitation of 2 GB
and when this limit is reached PST file get corrupted.
UNICODE PST file support upto 20 GB. To save ANSI PST file
from corruption better is to convert PST file to UNICODE.

Check this link
SysInfoTools PST Upgrade and Downgrade
for converting PST files.

June 11, 2011 9:28 PM

You will also need to export your rules to a file and import them in the new PST file. I notice mine were gone and had to do a 5 step dance to get them back.

August 15, 2011 8:00 AM

What about using the Import command?

Although you have to be careful with that too - when I converted my dad over I ran into some issues because his old files had actually somehow grown to larger than 2GB - so I had to go back to the old computer and old Outlook and split the files into smaller chunks before moving them over - man was that a long day.

Daniel Ford
June 15, 2012 6:32 AM

Quote: "You can avoid this and perform a true "copy" operation by holding down the Shift key when you drag and drop the folders."

Leo, are you sure this is right? It's contrary to the default Windows keys usage: -drag to MOVE, -drag to COPY.

Thanks otherwise for a useful article.

Daniel Ford
June 15, 2012 6:51 AM

Oops, your comment processor has removed my angle-bracket enclosed key names!

Shift-drag for MOVE, Ctrl-drag for COPY.

Comments on this entry are closed.

If you have a question, start by using the search box up at the top of the page - there's a very good chance that your question has already been answered on Ask Leo!.

If you don't find your answer, head out to to ask your question.