I'm currently using 32 bit Win 7 and Outlook 2007.

To take advantage of the ability to use more DRAM I want to convert to
the 64 bit Win 7 version.

I installed 64 bit Win 7. For the moment I cannot locate my OL2007
disks so I installed OL2003 as a temporary stop-gap. I copied the pst
file from 32 bit Win 7/OL2007 into the proper folder in the new Win 7 64
bit/OL2003 installation.

From within Outlook I go to File Open Outlook data file and when I
select the pst file from the OL2007 system I get the message that the
data file is not an Outlook file.

Is there some way to do what I'm trying to do? Have I done something wrong?

Any help is appreciated.