Incompatible version error

We recently bought the latest version of AutoCadLT.  At the same time, we bought a new laptop.  When I try to open any AutoCadLT file   created in a previous version of AutoCadLT, I receive an error message telling me that the file cannot be opened because it was created in an incompatible version of AutoCad.

How the heck can AutoCad be incompatible with AutoCad?

We've been running AutoCad and AutoCad LT for years.  Never had any such problem when upgrading from one version to a later version.

Please help.

Thanks,

Bill O'Donnell

Flint Hydraulics, Inc.

Memphis, TN 901-573-5472 (M)