I have two users running Windows 7 Pro that are both having this problem. When they print PDF's (stored locally on a file server of ours and/or from a website that a vendor provides us access to) nothing happens. Last week I upgraded them both to Reader X and that worked along with saving a copy of the PDF locally first. Today same problem.
When the user prints typically the processing window comes up then the document it sent to the Windows spool, but neither is happening. Nobody else is having that issue and we all are using the same printer drivers on Windows 7 machines. I thought about uninstalling the local printers and rebooting but have not done that yet. Also no other applications are having problems printing and each time Windows is able to print test prints.