Hello lenwah
Welcome to the HP Forums, I hope you enjoy your experience.
I understand you are trying to install your HP Deskjet 3050 on a computer with Windows 8? I would like to offer my assistance in resolving this issue with you. My recommendation would be to download and install the file DJ3050_J610_1315 which is the HP Deskjet Full Feature Software and Drivers for your printer and include the drivers for Windows 8. Be sure to read what I have posted below about installing before you install.
Internet Explorer:
Step 1. Before software download and install, make sure USB cable is disconnected from PC and device.
Step 2. Click the Download button.
Step 3. When a new pop-up window appears, click the Run button.
***Note: Depending on your connection speed, the file will take some time to transfer to your computer.
Step 4. If another pop-up window appears, click the Run button again.
***Note: The file is compressed and may take time to extract and run.
Step 5. Follow the on-screen instructions.
This should resolve your issue and get everything installed correctly for you. Thank you for posting your issue on the HP Forums. Have a great day!