CSxxxx error codes aren't TiVo-software but TV360-platform errors. TV360 is the same physical box as a V6, but completely different software. This therefore leads to one of two possible causes of this error...
1: You have intentionally converted from TiVo/V6 software to 360-software (bit hard to do unintentionally) and there's a problem with your account that's causing this.
2: You expected your replacement box to be TiVo-software-powered V6 but have been supplied with 360's
The box generating a 360-error would suggest your a/c is still expecting TiVo/V6, which lends weight to theory 2. There's a picture of the V6 here , and the 360 below.. The remote & the SW are the differences. Also a V6 has the TiVo-logo in the top-right next to the video preview, a 360 won't.
Edited to add: When you said your TiVo "expired" in your original post, I presumed that was slang for "went faulty" and has been replaced. I'm now wondering if you've had a sales pitch on 360 and were somehow told your TiVo was out-of-date.
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