Windows Media Player cannot play this DVD because there is a problem with digital copy protection between your DVD drive, decoder, and video card. Try installing an updated driver for your video card.

Now that's rather interesting.

The fact that a newer drive didn't have the same problems suggests, to me, that the WMP update deleted something in the registry which linked to my two drives so that it no longer recognized them as legitimate drives (or maybe, as suggested, found the virtual drive and decided something untoward was happening so the copy protection kicked in.

Personally I have given up on WMP all together. VLC is far better and free.

Microsoft isn't gaining any fans here when a simple update (and often done automatically via windows update) causes such problems.

A failing drive isn't my problem as they both work fine with several other programs so it must be the WMP update as one day it was fine, got the update, no longer working and no other adjustments etc made.

Of course, as usual, switching to an earlier version won't undo the changes made.

No wonder Microsoft is getting such a bad press. I've already had various problems with IE upgrades and other programs not being compatible with them (I've stuck to IE6 and I'm not moving - especially as I now use Firefox which I find far better).

Come on Microsoft, get it together.

I too had this same error when I found myself stranded out of town with a netbook and the desperate need for an escape from a grueling day behind the keyboard.  The solution for me was to use a newer DVDRW drive.  My failing drive was a Toshiba DVD-ROM model SD-M1212 and the sucessful drive was a Samsung SH-S202.  I am using an Acer netbook with an external enclosure by iMicro.  Oh and windows Media Player 11.0.6001.7000

Hope this helps someone.

I myself have been getting the dreaded Windows Media Player cannot play this DVD because there is a problem with digital copy protection between your DVD drive, decoder, and video card. Try installing an updated driver for your video card . 

But mine is a bit different, I work for a school district on a windows domain with Active directory accounts and the issue happens on teachers laptops, the weird thing for me is, if I logon as myself (tech account) the DVD plays fine, if I logon as local admin it plays fine (meaning not a profile issue).  I even tried creating a new local account with admin rights but it would not play on that account either.  I will try the windows media player classic thing later, but I am still stumpped as to why it will work on some accounts and not others, both on and off the domain.

Oh and I have klite already installed, did the driver things, firmware ect.  Windows XP SP3 WMP 11

My DVDs were playing fine until I had started running a Virtual Machine under VMware in the background. I use VMware to run a linux server on which I develop websites. One day, I decided to take a break from system admin and just minimized the VM. I popped-in my Red Dwarf DVD and proceeded to watch a few episodes. I didn't get very far. This message would appear after skipping though logos at the beginning of the DVD, just before presenting the menu animation.

I searched Google, found this thread, and bemoaned the possibility of having to buy something else just to play a DVD I have already paid for on a computer I have already paid for, in an Operating System I have already paid for... Anyway, I thought about the fact that I was still running my VM in the background. (I usually do not have it running when I watch DVDs.)

I shutdown my CentOS Server and closed VMware. Wow! My DVD now plays!!

Obviously, either VMware or Microsoft  or both of them need to iron this out... What are we to go back to the days of being able to run only one program at a time on our suped-up desktops? I am running Windows 7 64-bit with all current updates. I am running VMware 7.1.0, which I just purchased and installed the other day. It is the most recent version.

Just more food for thought... Good luck to those of you still suffering with this problem. My guess is that it might have something to do with a virtualization application or an application which virtualizes some piece of hardware being present. Maybe an ISO mounting application???