Please try these steps:
1. Press the SETUP button on your PIXMA MX492.
2. Use the left or right button to select Device Settings and press OK.
3. Use the left or right button to select LAN Settings and press OK.
4. Use the left or right button to select Wireless LAN Setup and press OK.
5. Press the STOP button.
6. Select Standard Setup and press OK.
7. Select your wireless network and press OK.
8. Enter your wireless network password and press OK. Please verify the password, as it is case sensitive and if entered incorrectly, will cause the printer and router to not communicate. To switch between letters and numbers, press the * key.
9. Press <OK> on the confirmation screen. The PIXMA MX492 will search for the access point.
10. When found, press OK on the Connected to the access point screen.