HP photosmart printer problems

I've recently upgraded my MacBook Pro to Mountain Lion. However I now find that it does not seem to want to wirelessly connect to my HP photosmart 5510 printer - the message says "network not detected" inspite of the fact that I've successfully downloaded the OSX 10.8 drivers from HP. The previous Lion OSX 10.7 software worked ok and I can use other wireless printers (e.g. Epson) elsewhere. The HP support site says that compatible software can be downloaded directly from Apple's app store but I can't locate it and if I did, how can this help if the HP drivers don't work? Any advice on how to solve this problem?