I have just imported my OE6 messages from a PC with Win XP to a new PC with Win 8.1.

I copied the entire OE folder to a thumb drive.  Before importing I changed the folder storage location in WLM.  I then imported the OE folders by the proper procedure in WLM.  I could see all the messages (approx. 2500) being copied across.  However nothing now shows up in WLM!  Where have they all gone?

I have checked the Windows Live Mail folder in File Explorer (in the new location as changed by me) and there is a file there: "Mail.MSMessageStore" 32.784 MB in size.  That is the only file of any size.