You open Microsoft Outlook and get an error message saying "Outlook could not open the file containing the folders used to send and receive e-mail messages, create appointments, and open the address book. Please select from the options listed below." The options given are to create a new personal folders file or open an existing folders file.  It might look as if your mailbox, appointments and address book are lost. They're not. Do not create a new personal folders file. Do not reinstall outlook.

Your .pst file (the file containing your data) may be corrupt or you may have exceeded its default 2Gb limit.

If the file is corrupt there is an Outlook repair program included with Windows which can fix the problem so you can access your email messages, appointments and address book again. The name of the file to run it is called scanpst.exe. If it doesn't start when you type it into start and run menu option use Windows Explorer to search for it. It may reside in c:\program files\common files\system\MAPI\1033. Remember you may need to include hidden files in your search.

When you start the program (scanpst.exe) it it will look like the screen shot below. You need to browse and select your personal folders file. This file is called outlook.pst. It is likely to reside in C:\Documents and Settings\Your user folder\Local Settings\Application Data\Microsoft\Outlook

Click start to run the utility. It will run through or a selection of eight phases. These include checking file consistency, looking for lost data and checking folders and items. Once it has run through the stages a screen shot like the one below will display.

Click repair.

Click ok once the program completes. You should now  be able to open Microsoft Outlook and access your email messages, appointments and address book.