That error message, normally, has nothing to do with 32 bit or 63 bit PC's. It usually reflects that the file you are trying to open in Family Tree Maker Version 11 (very old), was last worked on by a Newer Version of Family Tree Maker.
Did you just install Version 11 on your New PC?
How did you get your Family File from the old PC to the new one?
Also, you MAY have issues with Version 11 and the new PC, but that error message is different.