I spent some time today hacking around with codecs and the TivoToGo stuff, trying to get the video to play right. So here's the facts: a) .tivo files are proprietary formats, containing the MPEG-2 stream of a program in encrypted form, along with an identifying fingerprint, license statement, and creation date/time stamp. b) In order for the file to play, you MUST have a codec that can handle MPEG-2 installed. There is no such codec provided by default with any version of Windows. c) Only certain MPEG-2 codecs will work (currently) with the .tivo format. Tivo has listed some, but not all, of the compatible codecs on their website. I'm not sure yet what makes their format incompatible with some codecs, though it's probably at least in part the DRM stuff. d) Even if you DO have a support MPEG-2 codec installed, .tivo files may not play correctly! This is due to Windows automatically selecting what it thinks is the best codec to play a media stream. Chances are the file is being played with another codec entirely. -------- I had a pretty painless upgrade of the Tivo Series2 unit as well as my Tivo Desktop software. And I transferred a program from my Tivo to my home PC in about 9 minutes, over a wirless network connection. The .tivo file plays, but the video is stretched out. Sound is great though, and video quality looks fine. So apparently I'm not using a "compatible" codec. Like I get to choose which codec to play with, Tivo! I downloaded both the DirectShow Filter Manager and RadLight FilterManager tools mentioned here in this forum in an attempt to force Windows to use the proper codec. FilterManager has a nice interface, but doesn't actually change the Merit settings of a codec, so don't waste your time with it. DirectShow Filter Manager works pretty nice, though it's got a slightly kludgy UI. I had already downloaded the only codec for Win2K that Tivo listed as being compatible. So I installed AC3 Filter and surprise, it didn't do any good as the .tivo file still plays stretched out. I checked File|Properties of Windows Media Player and found the codec being used was MainConcept Video Decoder. Unfortunately, even after raising the Merit value of the AC3 filter, the .tivo file will not play with the correct codec. I even restarted my PC. No luck. So I do the next best thing, I unregister the MainConcept video codec and try playing the .tivo file again. This time, I get no video but I do get sound (and WMP complains about trying to download a codec but failing to do so). So I re-install the AC3 filter and try again. At first I thought I had succeeded because I got video this time, and the aspect ratio was right. However, the sound was very quiet, and the video contrast was too light (images with a lot of white in them tended to bleed out the rest of the image, and colors were all washed-out). I checked and discovered I was now using the CyberLink Video/SP Decoder (came with the PowerDVD player that I got with my DVD Rom drive). I ended up repeating this process multiple times. I'd unregister a codec, try and play the file, get no video, re-install the AC3 Filter and get video but not from the right codec. Both the MainConcept and CyberLink codecs were unsuitable for watching the .tivo file. However, the Nero Video Decoder and Nero DVD Decoder codecs worked quite well (they came with Nero 6 Deluxe). However, once I finished unregistering all the other MPEG-2 codecs besides AC3Filter, I could not get the AC3 Filter codec to play the clip. Which is quite odd, since Tivo is listing it as compatible. -------- e) MainConcept MPEG Video Decoder and CyberLink Video/SP Decoder codecs are not compatible with the .tivo format (at least under Win2K with WMP 9) f) Nero Video Decoder and Nero DVD Decoder are compatible with .tivo files under Win2K with WMP 9. g) There is some mechanism about unregistering and registerig codecs helps determine codec order. Unregistering a codec did not allow WMP 9 to automatically select the next available codec, instead it acted like it couldn't play video at all. The process of re-installing a different codec appeared to "refresh" the codecs list so that the .tivo file could be played with a new codec. h) The single most critical problem with getting .tivo files to play is getting Windows Media Player to select a correct, compatible codec. I think that last fact underscores the real issue here. WMP isn't going to let you choose a codec to use. Futzing around with Merits is a waste of time. Uninstalling and re-installing codecs might help but frankly should not be necessary and may have unintended consequences. The best solution would be to have a media player that can be configured to use a specific video codec when playing. Then modify the file types preferences for .tivo files to use that media player instead of .WMP 9. I haven't done that much research on it yet, so I don't know how possible this is. Hopefully I'll have some more useful solutions by next week.