What version of quicken are you using and what operating system.
Any version prior to 2010 may have problems printing under windows 7. Anything before 2008 will definately not print under windows 7.
If that is not the problem
file / printer setup / reports and checks
make sure that you have the correct printer selected there.
edit / preferences / quicken
UNCHECK the box next to "Warn on duplicate checks"
If that does not work
go to printers and faxes folder
highlight and delete by pushing the delete key on your keyboard the quicken pdf printer
from the windows start menu / search command
select search for all files
under advanced options
select search for hidden files and search in system folders
search for wpr.dat
rename any copies that you find to wpr.old ignore the warning that windows gives you.
reboot the computer
again go to file / printer setup
select the proper printer.
Please let me know if that works there are a few other things that we can try but those are the easiest solutions that fix the most possible causes.