Assuming your OS is Windows, you got to create an user account with the same name and caracteristics (administrator, or not) you were using before reinstalling the OS. If you still can't access your data, try and "take ownership" (google that) of the drive.
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Assuming your OS is Windows, you got to create an user account with the same name and caracteristics (administrator, or not) you were using before reinstalling the OS.
If you still can't access your data, try and "take ownership" (google that) of the drive.