Here's the Cheap Trick I mentioned ...
If you install a plotter driver (like an HP or a Canon) you can trick the computer by assigning it to an LPT port; even though you probably don't have one on your computer Microsoft still has them listed for a port you can select. The main idea is to get the plotter driver installed - you only use it to set your paper size and then use Dcad's built-in PDF for the plot.
You can also use this Cheap Trick if you DO have a plotter but it doesn't plot to the size you need (ie you have a 24" carriage plotter but need to print to a 30x24) - install a plotter driver that DOES support that size and then you can pick it!
Highest Regards,
Alan T. Hendry, RA
Intel i7-6700 (3.4GHz) Desktop, 32GB RAM, 3TB HD, Win 10 Pro 64-bit, DC 17, 18, 19, 20 & 21 w/ latest beta update
Intel i7-4702 (2.2GHz) Laptop, 16GB RAM, 1TB HD, Win 10 Pro 64-Bit, with DC 16 and all of the above