Recently I got a new laptop -HP Compaq nx6325. I partitioned the hard disk into three -C, E and F. I installed Windows XP SP2 in C and Windows Vista in E. Next was Office suite. I installed Office 2003 in C in the XP partition and Office 2007 in E in the Vista partition. I put the Outlook .PST file in F drive. Now I configured Outlook 2003 (part of Office 2003) and Outlook 2007 (part of Office 2007) to use the same .PST file. Surprisingly, both are working fine. Now I can work in XP or Vista and use my mailbox without any problem. I am thrilled.