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Thread ID: 44332	2004-04-16 04:21:00	USB ports - any XPerts?	andy (473)	Press F1

Post ID	Timestamp	Content	User
229609	2004-04-16 04:21:00	I added a DSE card reader to my PC. To do so, I had to disconnect two USB ports as the reader had to connect to the motherboard USB header. My Via P4PB MOBO has 6 USB ports anyway so I wasn't worried about it. Two of the ports are directly off the Mobo, and two headers fed two back ports and two front ports respectively, so I used the back port header for the card reader. Previously, I had my HP Scanjet 5370c scanner and my Brother HL1430 printer in these two ports, so I swapped them to the on-board ports. The printer worked fine but the scanner refused to communicate. I tried all other outlets, including the new one on the card reader, to no avail. I removed and reinstalled the scanner software but no difference. I reconnected the rear ports and connected the reader to the header that fed the front USB ports. Everything worked again! It seems that the scanner will only work on the one USB port (not even the other port on the same header!). I can't figure this out. I can't see any reason for this. Has anyone got any ideas? Could there be a voltage problem with all but one port? This is not a major problem to me, I'm just curious as to what's going on. I'm running XP home edition with all updates. The printer and other USB devices (camera and Ram disk drive) work on all other ports. When I said the scanner would not communicate, this is not strictly right. There is a push button on the front of the scanner to start the scan. This worked in all ports, but an error message "cannot communicate with the scanner" came up in all cases. Now that the scanner is working again, the push button function no longer works! This is all too weird!	andy (473)
229610	2004-04-16 04:35:00	Some USB devices do indeed need to be installed on each port used. The port on the card reader may well have a different enumerator due to the existence of the reader (unknown if the reader port is really a hub or not, but suspect it is) and may therefore appear as a different port to the one it replaces. This despite the fact that the card slots appear to be on a second separate port. Possibly uninstalling and reinstalling the scanner driver may not be enough to remove the reference to the original port entirely, it may take surgical action in the Registry to do that.	godfather (25)
229611	2004-04-16 05:04:00	Thanks for that Godfather. So much for "universal" huh!	andy (473)
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