Following a recent upgrade from vista to windows 7 I have received the following message when trying to open outlook 2003;

Unable to open your default e-mail folder. The file C:\User\Home\Appdata\Local\Microsoft\Outlook\Outlo ok(2).pst is not a personal folder file.

The only option available to me is an ok button which once clicked closes outlook.
Can anyone help with a way resolve this personal folder file issue.

Many Thanks
Alan