You will need to import the data into your current identity.

References:

Importing OE Data (all DBX files, including Folders.dbx)
http://www.insideoe.com/faqs/how.htm#importOE5

Importing a single DBX file
http://www.insideoe.com/faqs/how.htm#importdbx
http://www.oehelp.com/backup.aspx#imp1


DDC wrote:
I experienced a significant hard drive "event" and had to reinstall my
operating system. I was able to copy just about everything onto an
external
drive before reinstalling. I did not have the luxury of backing up Outlook
Express prior to the reinstall. I have been trying to figure out a way to
have OE now "point" to the old identities without any luck. I have moved
my
old dbx files into the identity that OE is now pointing to and it doesn't
recognize them. Please help! These files have years of mail history that
are
critical to my business. Thank you.