When this feature failed, a search of Tivo's web site turned up the following message (along with a statement regarding Windows 8 -- it's not supported). Smells suspiciously like a hard-coded date or algorithm issue -- a common junior developer mistake.
A more sensible workaround than changing the system clock for this bug is provided on Tivo Community.
As of February 16, 2013, the TiVoToGo feature of the TiVo Desktop application for Windows PCs is temporarily unavailable and no longer allows transfers from the DVR to the PC. All TiVoToGo-compatible TiVo DVRs are affected. We are aware of the issue and apologize for any inconvenience that this may have caused. We are working to restore this feature as soon as possible.While we work to restore this feature, a workaround is available to restore functionality. To transfer content from the DVR to your PC, please adjust the date on your Windows PC to a date prior to February 16, 2013. Please note that other programs and applications that depend on the Windows date and time settings may be impacted. Once the content has been transferred, it is strongly recommended that you restore the date and time settings to the current date.Other features within the TiVo Desktop application, other on-box DVR features, and Stream-related features are not affected.