Verify that your firewire adapter works first, not sure how you do this other than to find another 1394 device to test with, maybe an external Hard Drive. Then test your 1394 cable, if all that works and plugging your 3250HD into your PC still isn't detected then try to get them to switch out the STB.
The directions I wrote were actually worked out with a 3250HD from Bright House Networks which is basically TWC. I don't have the box anymore or I would check to see what the diag screen shows when it is enabled.
How good could it be if it isn't HD?
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