Unable to print coupons on target.com

I am having trouble printing coupons from target.com and some other coupon sites. Coupons.com site works fine. I have operating system 10.5.8 and a lexmark multifunction printer 2300. This is the error message I get :

" Unfortunately, you’re trying to print to a device that is not valid for printing coupons. Please check your print setting to make sure your default printer is a standard printer and has paper. If you have a multifunction printer (fax, copy, print), please make sure that “Printer” is set as the default function on your computer. "

Anyone solve this problem. I am no pro at computers and I"m trying to figure this out. I saw that there is a driver that can be downloaded but it's for operating system 10.6 so that doesn't help me. 😟 Any suggestions would be appreciated!

Thanks,

Bethany