What you want to do is reboot the player into ODIN mode. You do this by turning the device off, hold the volume down and power keys until you see the screen turn on. Immediately after that, push the volume up key and the screen should change. You should be in ODIN mode.
Then, you will connect the player to your PC and reflash the original ROM to the device using the ODIN Downloader for windows. If you have none of these files (ODIN Downloader and/or original ROM files), let me know and I will get them to you somehow.
After you have done this, you will have the original ROM and recovery flashed to the device.
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