Sorry that you are having a problem with the new network.
You will just have to reconfigure the wireless settings.
Here is a link that may assist you.
If you do not have the CD, here are some directions. (Convert USB to Wireless).
1. Plug in the USB cable.
2. Click on Start Menu
3. Choose All Programs
4. Select HP folder
5. The printer name
6. Go to Wireless Configuration or Convert USB to wireless.