Lost Email saved in folders and sub folders

I recently upgraded from Windows Vista 64 to Windows 7 (64). Part of the upgrade included Office via group license. Windows Live Mail 2012 included...upgrade from the Live Mail 2009..think that was the past year.

Transfer of stored Live 'e-mail went relatively easily.

Recently however, when going to retrieve old mail or recently stored mail in both old and new folders/subfolders, a message comes up " Message cannot be found-content of this message cannot be found" OR I find the email in another old or newly created folder.

Any suggestions on what to do to rectify the problem? Thank-you.