Instructions
Click "Start" on your computer. Then select "Run." Windows Vista users can type in the word "run" to pull up the program. After you open the program, type "CMD."
Type "IPCONFIG" on the command prompt and press "Enter." The screen will display your network settings. Write the number down next to the line "Default Gateway."
Close the "Run" program and open a new Internet browser on your computer. Type the DNS number you wrote down into the address bar and hit "Enter." You'll be taken to a site for setting up your connection.
Click the menu selection on the right side of the screen that says "Wireless." Next click the option for registering a new station.
Name the new station and you will be asked for the Mac address. Power on your PSP and select "Network Connection." The console will show the Mac address under the network settings. Enter this address into your computer browser.
Submit the information and your PSP will be a registered device. Now connect to the Internet with the handheld and you will not receive a DSN error.