I also have been experiencing the "Restricted Content" error. It started sometime on Wednesday, 5-14-08. The only windows updates I had received prior to that date upto a week ago were for Windows Mail. I have not seen the above mentioned update for the ATI DCT. I didn't notice the issue had occured until Friday, so the several recordings between Wed to Fri evening all had the same error.
In attempt to correct the issue on Friday, I rebooted the computer and the DCT. This allowed Battlestar Galatica to record, however shortly after that it failed again. In an attempt to fix the issue, I downloaded drivers from Dell for my video card (ATI HD 2600 XT) and updated the bios to REV A04. This didn't correct the issue. I then upgraded the firmware on the DCT from 1.16 to 1.17. This also didn't resolve the issue. Finally i upgraded to Vista SP1. This also failed. I made a manual backup of the current state of my XPS 420 using Windows Home Server and then rolled back to Tuesday's 12:00am backup. This too did not resolve the issue.
It seemed to me then that it probably wasn't an issue with software or drivers being installed so I rolled forward to the SP1 backup and then contacted my cable company (BrightHouse, Tampa Bay) and had them re-pair both cablecards. We followed the proceedure MSFT had outlined with the HIT following several minutes behind the INIT msg. This resolved the issue for approx. 24 hours. To be upfront, I also had opened the advindex of both DCTs and turned on tracing during the entire time period. I have saved those logs. I also had a recording scheduled on both tuners constantly. I had them randomly alternating between true HD recordings/channels to regular standard defs, using TNTHD, TBSHD, HDNET, HDNETMV, SCIFI, and several local HD and non hd channels. The issue did not resurface until the last recording was being made on TNTHD for "The Truman Show." The recording failed exactly 45 minutes in to the 12:00pm airing. As I can tell using the traces, no error message showed that corresponded with the failed event. I could post the full logs however if anyone would like. On a side note, this did repair the "issue" i had with not ever being able to tune into TNTHD, prior to Saturday, I never was able to tune to it. But I rarely wanted to watch anything on it as the commerical breaks usually were odd, and movies tend to be compressed and randomly in stretch-o-vision.
Currently, I've rebooted the system and the DCTs again and have set several recording for the rest of the evening. We'll see how things progress. It should be noted, I've had this system installed and functioning without a single incident since late Feb. Not one missed recording, and not a single failure in any way. The system had a relibility rate of 10.0 out of 10 and even when the DCTs cablecard light turned red, it still recorded fine. All of this on the 1.16 firmware and a essentially factory image installed on the XPS from Feb, with the only additon being the WHS connector and disabled virus scanner and windows defender. I also only used the computer for TV recording and serving to the Xbox 360. I rebooted between once a week to once every 3 weeks, depending on when I needed to clear the red light on the cable card. I also let automatic updates come in, so if there were other reboots in there, I didn't witness them. In fact, I didn't have a single install problem or hiccup outside of never being able to tune to TNTHD, which for me was a non-issue, so I counted myself very lucky when I got the system up and running... Alas now it seems a lot of us have joined a newer club... "Restricted Content" for no apparent reason whatsoever. I know several people had an issue on Monday's NBC lineup, but I don't even record anything on NBC at this point in time so my tuners haven't tuned to NBC since the last episode of Chuck...
At this point, I still have a cable tech coming on Monday, but it seems pointless, because just about everything seems to fail at some point. I'm wondering if this a indication of a larger issue. Some sort of timebomb, not from the cable companies, or the computer makers, but perhaps an issue on the Microsoft/CableLabs DRM end. I assume that the cablecards as part of the their DRM/Activation scheme call home to some where at x intervals. If that is truely the case, perhaps the server is responding with invalid data or is invalidating/revoking the systems that ping to it? The only other explanation I can come up with that would work with so many of our systems in this extremely varied ecosystem we have going is that perhaps somehow all of our computers have gotten a virus that is targeting these setups. I'm sure alot of us don't run virus scanning to avoid interference with the DCTs, so while this idea to me seems farfetched, it is somewhat plausible. Of course, there would have be something common with all of our connections however for the virus theory to work and since I don't surf with mine, unless it was able to infect this computer and then travel to my other, it seems doutful at best.
Long winded, but maybe someone else watching can make use of my observations. I'd really like to see this issue resolved for us all asap.. Especially with finale week underway :(
-Ripley