Hello there and welcome to the forums,
As I understand, you are unable to print from your computer to your Officejet 4500. Please respond to me with some more information and I will be happy to help you.
1. Which 4500 do you have?
- HP Officejet 4500 All-in-One Printer - G510g
- HP Officejet 4500 Desktop All-in-One Printer - G510a
- HP Officejet 4500 Wireless All-in-One Printer - G510n
2. What OS are you running?
Which Windows Operating System am I running?
Mac OS X: How Do I Find Which Mac OS X Version Is on My Computer?
3. How is your printer connected? USB, Wired (Ethernet) or USB?
4. When you attempt to print, do you see any error messages? If so, what do they say?
Thank you,