If you're using MPASMWIN as the assembler, make sure you have the latest version of
MPLAB installed with the P12F615.INC header file.

You could also try switching to PM as the assembler for a quick check.

If you upgraded from an older version of PBP that may be a problem too if MCS is still using
the old version at compile time. Support for the 12F615 was added in version 2.50.