Problem is fixed.

My original include files looked like:


Code:
INCLUDE "vars4.inc"
GoTo Initialise
INCLUDE "DT_INTS-18.bas"
INCLUDE "ReEnterPBP-18.bas"     ; Include if using PBP interrupts
INCLUDE "NewRXbuff.inc"
INCLUDE "Init18_4.inc"
INCLUDE "Rxmsg18_1.inc"
INCLUDE "Scan2.inc"
INCLUDE "Display4.inc"
INCLUDE "Process18_4.inc"
INCLUDE "MonMode_1.inc"
INCLUDE "MSSP.inc"
Whilst the Goto immediately after "vars..." may look strange, it was done this way many years ago when the project used a PIC16F876. I can't remember the reason for doing it this way but it always worked when assembling with PBP so there has been no reason till now to change.

With this new version of the project using a PIC18, by removing or moving the Goto the project now compiles/assembles without error. My includes are now:

Code:
INCLUDE "vars4.inc"
INCLUDE "DT_INTS-18.bas"
INCLUDE "ReEnterPBP-18.bas"     ; Include if using PBP interrupts
INCLUDE "NewRXbuff.inc"
INCLUDE "Init18_4.inc"
INCLUDE "Rxmsg18_1.inc"
INCLUDE "Scan2.inc"
INCLUDE "Display4.inc"
INCLUDE "Process18_4.inc"
INCLUDE "MonMode_1.inc"
INCLUDE "MSSP.inc"
It still puzzles me why the PIC18 project worked perfectly until I added shift functions which then caused MPASM to generate errors.

mackrackit, thanks for trying to help.