This has been the cause. Just a list.

1. SP2 was required. I have an old machine that the drivers will fail to install on SP3. I have to write a note to myself about that and put into the driver CD sleeve so I remember that.

2. An antivirus suite, firewall can interfere. Disconnect the internet and try again without those.

3. There is an order which drivers must (shall!) be installed in. Example: OS, Motherboard driver package, Sometimes the MSUAA then the sound driver. More at and you can google up MSUAA and Dells.

4. A corrupted download. Can be your AV suite or a download accelerator.

Hope this helps,