I'm bringing up my milling machine after replacing the WinXP PC with a Win10 one and SmoothStepper.  I thought I had everything dialed in, so I ran a program (admittedly a new one I'd never run before), and it stopped mysteriously about 85% of the way through (line 4990 out of 5660).  I can't figure out why.  I've attached a screenshot of Mach 3 showing the line it stopped on, a copy of the G code (generated by Cut2D from my drawing), and a photo of the part after the machine stopped (it was milling out that central pocket).  Also, the spindle stopped gradually, like it was using Mach 3's deceleration parameter, not abruptly.  Any ideas?

PS - I realize the cutout profile should have been cut last, but in my zeal to get the program running I didn't realize I saved it in the wrong order.  The tabs held everything together just fine, though.

PPS - The uploader keeps telling me there's already an attachment with the same name as mine (even though they all have different names).  I've tried uploading just a single attachment but it gives me the same error, so I'm afraid I can't upload any attachments.  I've even tried uploading a single attachment as a reply to this post, to no avail.  Any tips on what's causing THIS problem?

Rename and give each of your attachments a unique name eg. Involute1a, Involute2a, etc.

This thread refers;  https://www.machsupport.com/forum/index.php?topic=24585.0

Tweakie.

Aah, thanks.  Here they are.

Since my initial post I've noticed that, in the Mach 3 screenshot, line N5000 is endlessly repeated, so I assume that's the problem.  Maybe not, but, regardless, what would cause that?  You can see in the code in the pdf that that's clearly not how it's written.  I'll load it up again tomorrow, scroll down, and see if I can duplicate it, but I've never seen Mach 3 do that before (change code in that way). 

What is your Mach3 version?

On Version R3.043.062 everything looks fine.
Attached is code from your .pdf

It looks very much like your license has not been accepted and Mach3 is stopping at line 500 (as it would in Demo Mode).

Perhaps re-install you Mach3 license.

Tweakie.

Tweakie, it is visible on the screenshot that the license is present: Richard Lowe

GCode window without and with license, no differences. W/O license Mach should stop at line N5000, have not tested

Tweakie, it is visible on the screenshot that the license is present: Richard Lowe

Hi ZASto,

Indeed it does, but that does not mean that the license has been accepted by Mach3.
(Running the Gcode file in Demo mode stops at the same line #4990).

Tweakie.

It stops, but it does not replicate line #5000 until the end of time

Aah.  I’ll recheck the license today.  I don’t know the program version off the top of my head, but I downloaded the demo version in the last week.