Meta data wants to be mapped elsewhere when importing assets.

Hello all, When importing some assets I occasionally receive this error: Error importing folder (The pathName assets/[name of asset folder] is already mapped to 36fdbd97f2d3a e74b93aa4169625f9ed. But the meta data wants it to be mapped to 81ad00acabd02304990814095cb90da2). It seems, on import, Unity wants to put some files in other locations that do not exist. I only receive the error sometimes - when importing into a new project. Anyone know why this might be, or how to fix it? Thank you for any help. ;)