You may not be able to do so. ''It is important to not write anything back onto the drive.''
There are a number of data retrieval apps that depend on what OS you're using.
The process is that you make a copy (if possible) of the data onto a good working backup volume and then retrieve data from there.
''As a Mac user I have had good results from DataRescue3, and also from Cardwiper ''an app. that has a retrieval function.
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