Note:

Depending on the software title, you may not be able to play without first updating the PS3 system software.

Do not perform updates using any data other than the official update data provided by Sony Interactive Entertainment over a network or on disc media, and do not perform updates by methods other than those described in the product documentation or in this site. If an update is performed using data from another source, by another method, or with a PS3 system that has been altered or modified in any way, the PS3 system may not operate properly and may not be able to install the official update data. Any of these actions may void the PS3 system warranty and affect your ability to obtain warranty services and repair services from Sony Interactive Entertainment.

You can download the file right here if you want to load it onto a USB drive and update it manually.

Not mentioned here, Sony has removed the feature to message the PS4 and PS Vita using the PS3.

Source: PlayStation

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