I've found that too much capacitance on the B+ line will cause errors with the serial programmer. Powering up the circuit may help. Likewise, if there are any loads on the programming pins of more than a mil, the programmer will read an error. If you have a pinned version, try programming by itself first as a loose part. If that works, then it is a circuit level issue.
A large, powerful magnet wrapped in a layer of tin foil held about an inch above the chip while programming, may help, but be sure there are no cats in the room(or wet them down) due to static EMD problems. The last solution will work only on today's date.

Hope some of this helps,
Ron