USB drop outs copying files from Memory Cards


New Member
My desktop PC has a problem with it's USB ports which can be summed up as follows:

* General devices (mice, printers etc) run fine
* My Camera's (when directly connected), USB memory stick & Card reader work fine when connected to my laptop.
* The same devices when attached to the desktop machine connect OK and appear fine when connected and browsing directories etc.
* As soon as I copy (significant fast data transfer) from the same devices the "port" hangs. There is no apparent disconnection but the transfer fails with a "could not find this item" error and if I then browse the device it tells me there are no files or directories contained within it.
* A physical disconnect & reconnect gets me back to an apparantly OK connected device.
* USB drivers & BIOS up to date.
* USB ports deleted and recreated in device manager.
* Running Vista Ultimate 64-bit SP2 - all updates installed.

Any thoughts? Would a firewire card & reader have the same problem? With a Canon 5dII generating huge files, having to copy everything to my laptop and use the wireless network to move the files to the desktop is a right pain in the backside.

All help gratefully received.

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