Here's the situation:

PC 1 has emails in Outlook Express folders that require transferring to Outlook Express on PC2.

Simply exporting and importing is not the answer as it would overwrite the inbox.dbx (and other matching .dbx) email data currently in use on PC2 (right?)

How would you approach this?

Got a feeling it might involve renaming .dbx files at some point so that PC1's Inbox Folder would become an Old Inbox Folder (i.e. inbox.dbx -> oldinbox.dbx), then finally moving individual emails to other OE email folders as required from within running OE itself.