Issue with Outlook PST files and Windows7

At last I have an evening to sit down and have a go at writing this blog, we have had a couple of issues come into the Service Desk over the past week to do with PST files.

So what is a PST file?  This is an excerpt from the Microsoft Knowledgebase on PST files - "The Microsoft Exchange Server 4.0 team created .pst files in order to let users maintain a copy of their messages on their local computers. The .pst files also serve as a message store for users who do not have access to a Microsoft Exchange Server computer (for example, POP3 or IMAP email users)."

I would point out that your Exchange Mailbox and PST folders should NOT be used as a document store, they were never designed for that.  Think of those little metal mailboxes you always see being driven over in American movies, now think about you trying to cram in all your letters over the last five years into one of those little mailboxes - something will have to give...

The first issue came when we were migrating a user from Windows XP to Windows7 - it was noted that the PST file was over 5Gb, we couldn't actually move the file, it kept corrupting during the move, the scanpst tool kept falling over, therefore all we could do is create another couple of PST files and move the messages from the origional to the new folders.  The maximum supported PST file size in Outlook 2003/7 is 2Gb.

This brought on the second issue, when creating a PST file in Microsoft Outlook 2010, the default location was  the_users_home_drive\My Documents\Outlook Files, this on our network, it is a network share that is syncronised to the users laptop.  Creating the file was fine, but as soon as we started copying messages to the new PST folder, Outlook would freeze, using Task Manager, it was not possible to stop the Outlook Process and you could not shut the laptop down.

My theory on this is that, because Microsoft have improved the Windows7 syncronisation capabilities, as soon as the PST file 'changes' because a message has been copied to it, it starts to automatically sync the file, thus causing a conflict.

The resolution was to turn the laptop off, switch on again, go into the Account Settings and remove the network PST file and create a new one on the local C: hard disk.

Within our organisation, we have chosen to keep all the users local files in the C:\Users\Public\Documents folder.  Keeping the PST files locally on the users hard disk is the recommended location according to Microsoft in its Blog Network Stored PST files ... don't do it!

So if you want to create a PST file, so that you can store Outlook 2010 messages outside of your Exchange mailbox you need to follow thes steps:

1. Within Outlook, click on the File tab.
2. Click on the Account Settings Button then click on Account Settings from the dropdown list.
3. In the Account Settings windows, click on the Data Files tab.
4. Click the Add button.
5. The Explorer window now opens. Do not choose this as your location, this could be a network share!  Instead use the left hand navigation to choose the C: drive and navigate to C:\Users\Public\Documents  - put in a filename that suits you and click the OK button.
6. You should now see a new folder in the Left Hand navigation pane of Outlook with the name of your PST file, you can start draging/dropping messages from your Inbox to the PST folder.

Be aware!  Always keep an eye on the size of your PST files - Microsoft have increased the maximum PST file size in Outlook 2010 to 50Gb - Knowledge-base number 982577 - but from my point of view a 50Gb PST file will take ages to backup and if it gets corrupt you have lost a whole load of mail, so I would tend to keep the sizes to more manageable limits.