If you get the image from ggieseke, it may have to be updated before it will boot on a 4TB drive. My suggestion would be to use DvrBARS to put the image on any good drive that is less than or equal to 2TB and boot it in the TiVo. Force a few connects to the TiVo servers to get it to download and install the update. Once the image is updated, use MFSTools 3.2 to copy and expand the image to the 4TB drive. The JMFS method will only add 2TB of recording space to the original image.
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