I beleive this only works with Outlook 2007 and later.

To attach a data file to existing email/personal folders in Outlook:

Tools>Account Options/Settings>Data Files..
Find the one you want and check where it is located

Go to:
File>Open>Data file…
Navigate to directory that we found in the step above, select the data file (or .pst file) and and click open

This will load it on the left along with your personal folder and inboxes.

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If you are trying to do this on an earlier version of Outlook, there is another way to do this.

Go to Control Panel>Mail

Click the Data Files button

When the window pops up click on ‘Add…’

Navigate to directory that we found in window that popped up before, select the data file (or .pst file) and and click open

This should have the same result as above and is a bit quicker.

 

OG