Exporting your data essentially creates a back up of all current information found in your mailbox. it is also recommended check the size of your mailbox data.



If combine your data is close to 2gigs of information export only your emails to a .PST file and export calendar and contacts to a .CSV file. This will eliminate the possibility of corruption.

If you currently have a .PST you can simply import that file and all data will be uploaded to Outlook 2010.

Note; If your current .PST is a back up of a previous date it will only contain data up to that date stored.

hope this helps.

I have saved my outlook 2003 pst folder on af USB harddisk before upgrading to outlook 2010. After having upgraded (win7 & office2010) - and opened Outlook 2010 - I whant to manually open my old outlook 2003 datafile within outlook 2010 (file - open) - but I got the following error message: "There was denied access to the file. You do not have the necessary permissions to access the file." (Translated from danish to english via Google). Do somebody know why I can´t open my old 2003 pst folder?

Did you attempt to import this data file using the standard File > Open > Import?