To fully understand it, let's recap a bit. In the text below I'm talking about the situation in Europe, as I'm not well versed in the whole US television situation.
Originally, MCE only had support for analog signals, either from antenna or analog cable installations.
Then, in Windows Media Center 2005 (the XP version) roll-up 2, support for DVB-T was added - I believe pressure came mostly from the UK market where Freeview (a non-encrypted free DVB-T service) was launched. In other countries, the DVB-T offerings often carry encrypted signals. There is no official support for encryption in MCE, so the drivers of the card had to sort support for a CI-slot out by themselves. Several cards appeared on the market that could do this. The behaviour of MCE is a bit weird though when it comes to encrypted channels - it will not report finding them during a channel scan, but if you go to the config page where you can add/remove channels, you will see them listed as deactivated. Simply activating them will work. The DVB-T card should use some proprietary software to decrypt each channel as you select it for watching or recording.
Of course, people wanted to use DVB-C and DVB-S(2) cards on MCE as well. Without any official support, the drivers of these cards had to be clever and present themselves to MCE as DVB-T cards. That's easy enough, but the drivers also have to translate frequencies. MCE will scan the typical DVB-T frequencies. The driver has to translate these frequencies into values that are meaningful for cable or satellite. The popular Digital Everywhere tuners (now sadly unavailable) work this way. There's a table in the registry, listing the DVB-T frequency and the target frequency (or transponder, polarisation etc. combination for satellite) that you want this particular frequency translated to. That works fine. Of course, the whole encryption thing also needs to be active.
In Vista, the situation continued unchanged - no support for anything but unencrypted DVB-T. Talk about progress! The release of the TV Pack changed this, but this was done so late in the game that Windows 7 was already around the corner.
In Windows 7, there's official support for DVB-T and DVB-S(2). The latter even supports DiSeqC, so you can use a dish with up to 4 LNB's to receive four satellites at once. I do believe encryption is still unsupported so the manufacturers still need to provide proprietary solutions for that. The support for DVB-C is still missing. A bit weird, with all the other stuff in place supporting that standard would be trivial. But it's not there so you still need the old "pretend to be DVB-T" trick. On my machines, the Digital Everywhere DVB-C tuners work fine that way, HDTV and all - they're also carrying AlphaCrypt CAMs to decode the encrypted signals. Windows 7 supports my 4-LNB satellite dish just fine.
It should be noted that apps like DVBViewer support all forms of DVB cards with CI-slots. I always have that software installed to check whether the cards are working properly. You can even see the "pretend" drivers in action, as my DVB-C tuners report themselves as DVB-T. It's easy to get confused...
If you have problems with DVB-C in MCE, be sure to check the following:
- Do you have MCE-aware drivers installed? As you can see, some trickery needs to be performed.
- Do you have software installed to handle encrypted channels if necessary?
- If you have the right software installed, is the frequency translation table properly configured? Can you alter the frequencies?
- Does the frequency translation table list the correct symbol rate and QAM value? If these are incorrect you won't find anything.
- If MCE still reports finding no channels, have you checked the guide/channel configuration page for encrypted channels that have been found?
- Does your cable provider encrypt all channels? If yes, do you have the right CAM/smart card combination?
I hope this helps. Of course, the suggestion made by Florisel is good too. However, you will need one DVBViewer installation for every virtual tuner in MCE.
