DVDs won't play - software or hardware problem?

Sorry, I am not even sure whether it is a software or hardware problem.
Today I installed PowerDVD (first I tried ver.5, then ver.4) but it refuses to play DVDs.
I keep getting messages "Error Code: 89030000 - Unknown file format".
PowerDVD's Information tab reveals the following:

Player & Display information: not available
Hardware information
3DNow! Technology: not detected
Enhanced 3DNow! Technology: not detected
3DNow! Professional Technology: not detected
IA MMX Technology: in use
Video Accelerator: ATI Hardware Video Acceleration (not in use)
Multispeakers Audio Device: not detected
Spdif Output Device: not detected

I also can't play audio CDs, while DivX and BSPlayer work perfectly!
As far as I know I correctly installed all software and hardware, therefore I suspect that PowerDVD isn't compatible with ATI graphic cards. On my old PC with GF2 graphic card I had no such problems.
DVD-rom audio I connected to CD-in connector on my soundblaster, since I didn't find the digital audio cable (which I could connect to spdif).
Please help!

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Win98se, Abit IS7, P4 2.60c, 512MB DDR433, Sapphire Radeon 9600 Pro, Audigy2, Creative Inspire 5.1 digital 5500, Teac DV-516E (DVD-rom as secondary slave), Teac CD-W552E (as secondary master).

 

This might help you a bit let me know if it works

http://www.gocyberlink.com/english/cs/support/faq.jsp?ID=1233\


note the patches at the bottom of the link for power dvd

 

Endiablado, thank you for this link!
I'll download those patches tomorrow and try the suggested actions.
A report follows.

 

I am interested in knowing if they worked let us know

 

Well, here it is!
I've done all the tests and updates suggested by Cyberlink, but they didn't solve my problems. I kept getting the same error message.
Then I compared audio/video compression codecs between my old and new PC and found them to be the same.

Finally I tested two other DVD players and they both worked: BlazeDVD and SuperDVD Player (however, both of them lack the pan&scan option).

Conclusion: Teac DV-516E is not compatible with PowerDVD players!

Now, I was told that Teac was not what it used to be, but I couldn't get any older model.
I have to decide whether to purchase a new DVD-rom (definitely not Teac) or a new DVD player (say WinDVD).