I think that I follow what you are saying but I can't understand why it should be. You have checked that the cable is still working? It's just that I would have thought that one side would be powered maybe and the other not.
Some test results here...
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[Not Working]WDP250 -> Cable-A -> UD3R
[Working]
WDP250 -> Cable-B -> UD3R
[Working]
WDP250 -> Cable-B (without connecting the "power-only" cable to another USB port) -> UD3R
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[Working]
WDP250 -> Cable-A -> Laptop (bought in 2008)
[Working]
WDP250 -> Cable-A (without connecting the "power-only" cable to another USB port) -> Laptop (bought in 2008)
[Working]
WDP250 -> Cable-B -> Laptop (bought in 2008)
[Working]
WDP250 -> Cable-B (without connecting the "power-only" cable to another USB port) -> Laptop (bought in 2008)
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[Working]
WDP250 -> Cable-A -> P4 system with old Gigabyte motherboard (bought in 2004)
[Working]
WDP250 -> Cable-A (without connecting the "power-only" cable to another USB port) -> P4 system with old Gigabyte motherboard (bought in 2004)
[Working]
WDP250 -> Cable-B -> P4 system with old Gigabyte motherboard (bought in 2004)
[Working]
WDP250 -> Cable-B (without connecting the "power-only" cable to another USB port) -> P4 system with old Gigabyte motherboard (bought in 2004)
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