Here is the "preamble"

M106 S0
M140 S60
M104 S204 T0
G28 ;move to endstops
G21 ; set units to millimeters
G90 ; use absolute coordinates
M82 ; use absolute distances for extrusion
G92 E0 ; reset extrusion distance
G1 E-4.00000 F900.00000 ; retract
G92 E0 ; reset extrusion distance
M190 S60
M109 S204 T0
G92 E0 ;zero the extruded length
G1 F200 E3 ;extrude 3mm of feed stock
G92 E0 ;zero the extruded length again
G1 F12000

Thank you for the suggestion. I now have Cura set to TO. It has become an intermittent problem. It was skipping the heating for a while on every print. Now it is working sometimes. And yet I can get it to work by entering the command on the send g-code box or by typing in the number and pressing enter. Odd.

Hi, I am having a (new) strange issue whereby my hotend is not heating from a .gcode file. I am connecting to my Duet via wifi and I use the web interface to upload gcode to the printer. gcode is produced by CURA. When I launch a .gcode file, the bed heats up, but when it gets to the "M109 S205" line, I get an error code saying that there is a hotend fault. However, I can get the hotend to heat up by either typing 205 into the GUI or by entering "M109 S205" into the send gcode area. I have full control over other parts of the printer. I can't understand why or how I could be able to heat (or cool) the hotend by entering values, yet it doesn't work when running a .gcode file.

thanks