All of our users are using Office 2003. We have one user that has a large Outlook .pst file. It has been archived and it is still almost 4 gigs. Before we archived it, it was 18 gigs. Outlook has crashed several times and we have had to reinstall it and then open up his .pst file and set up all of his email accounts. We are looking at buying a new laptop for him with Office 2010. My question is will Outlook 2010 handle this large of a .pst better 2003? Will there be issues importing everything in to 2010 from 2003 like the .pst file? Will there be any issues interacting with word documents and spread sheets from the other users using 2003? Will the users be able to open his 2010 documents using Office 2003? Thank you for your input!