Here's a thought or three. I'm not sure if this would do it, but it certainly seems possible and is worth taking a look at.
The A3 paper size, used in the snip of code you showed us, is a European reference to paper which is ROUGHLY the size of 11 x 17, but not quite. The code is printing in landscape and telling the printer to format printing as if it has paper installed that is 11.7 x 16.5 (A3 size). If indeed you have 11 x 17 paper in the printer, there would be an overflow of printing at the bottom of the page equivelent to .7 of an inch, thus causing a flow of text over to another sheet of paper (printers are dumb ya know). The same would happen if A4 was used in the code and you put 8-1/2 x 11 paper in the printer, except it would happen on the right margin, not the bottom in landscape. The A4 size is actually 8.3 x 11.7, so the document printing would underflow by .2 of an inch at the bottom (in landscape), but would overflow by .7 in on the right margin. All of the margins in those print settings are extremely tight, so there's no room for any "slop over". ;)
Now, let's take this one step further and see if we can explain why it works for some people and not for others. What if.....
What if the users who do NOT have trouble printing with this macro have gone in and set their default printer settings on that particular printer to something slightly different than the people who DO have trouble printing? What if one group or the other has left their default print settings to "auto" and the other group has set their default print settings to, say, tray 2 always contains 8-1/2 x 11 and tray 3 always contains 11 x 17, thus overriding any programming settings?
These are all just thoughts running around in my head, but it's certainly worth a shot at looking into the possibility of this little "ditty" causing the problem.
So, when you get a chance, I would change that code to get rid of the European paper size references if it is indeed being used here in the States, as your location indicates. Here's some of the codes that CAN be used instead of [b]xlPaperA3[/b]:
[b]xlPaper11x17[/b] (for 11 in. x 17 in.)
[b]xlPaperTabloid[/b] (for 11 in. x 17 in.)
[b]xlPaperLedger[/b] (for 17 in. x 11 in.)
[b]xlPaperLegal[/b] (for 8-1/2 in. x 14 in.)
[b]xlPaperLetter[/b] (for 8-1/2 in. x 11 in.)
[b]xlPaperNote[/b] (for 8-1/2 in. x 11 in.)
Anyway, hope this helps. Let us know what you find. :)