I have a Dell optiplex running win7 64x that can't print to any network printers, the only thing it can print to is a PDF writer. This is one PC in an office with about 15 other PCs and it's the only one that has printing issues. I don't know if it's causal or coincidental, but just before I had these problems, I uninstalled their Kaspersky Antivirus and installed Webroot AV. I did try to remove the Webroot, but it didn't help. Also, the LogMeIn remote support software stopped working. It has connectivity, it can browse the internet and it can access network shares and I can ping the printers successfully.
It has multiple network printers, and I've even installed a new one (I picked up the PC from the client and brought it to my office and installed my network printer on it, with no luck).