Some time ago, Microchip had an error in the P18F4550.inc file.
It was corrected in subsequent versions, so you are probably using an older one.

From the file ... C:\Program Files\Microchip\MPASM Suite

Code:
; these are correct
_FCMEN_OFF_1H        EQU  H'BF'    ; Fail-Safe Clock Monitor disabled
_FCMEN_ON_1H         EQU  H'FF'    ; Fail-Safe Clock Monitor enabled
Was originally spelled ...

Code:
; these are not correct
_FCMEM_OFF_1H        EQU  H'BF'    ; Fail-Safe Clock Monitor disabled
_FCMEM_ON_1H         EQU  H'FF'    ; Fail-Safe Clock Monitor enabled
You can just correct the spelling to fix the error.

And you should not be renaming MPASMWIN executables.
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