Hello I am Angilina Ken. If you face the "HP Envy 4500 offline" error, here are some steps you can try to resolve the issue. Check the power and connection of your printer to make sure it is properly connected to your network. Restart your printer, computer, and router to clear any temporary connectivity issues. Update the printer's firmware to the latest version, which may resolve the issue. Run the printer troubleshooter to identify and fix any software issues. Change the printer's IP address to resolve any IP conflicts on the network. If these steps do not resolve the issue, try contacting HP Support for further assistance. It's important to note that resolving the issue may vary depending on the specific model and software version of your HP Envy 4500 printer.