1.    On the PS3 system XMB, go to the   (PlayStation Network). (Skip this step if you are already logged in.)

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2.    Highlight   (Account Management) and press the   button.

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3.    Highlight [Redeem Codes] and press the   button.

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4.    Enter the code printed on the voucher or PlayStation Network Card. The funds or item will be added to your account.

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Please not that the code is case sensitive. Be sure to enter the code exactly as it is printed. Using the on-screen keyboard?Learn How

5.    Once the voucher is entered, games will appear in the Download List.
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Or go to the Sony Support page