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USB Ports not Starting

HP Recommended
HP Z620
Microsoft Windows 7 (64-bit)

Hi There,

                Hope to find some help here. I’m experience an unusual behavior on my Z620 Workstation, I’ve a couple of External Hard Drives attached to it, one on USB 3.0 with external Power and a USB 2.0 self powered, when I turn on the machine they do not show up on “my computer” but they are show up in the Device Manager under Disk Drives and also show up on Disk Management but with our Drive Letters, if I unplug them and plug them again they now show up. I also enter to the BIOS and they are acknowlege there (Both Drives on each external USB Plug)Disk ManagementDisk ManagementDevice ManagerDevice ManagerBIOSBIOS. I’ve been a computer user for many years and this is the first time I find this behavior.

                Thanks and hope to heard back soon



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Message 2 of 2
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HP Recommended

Hi to you as well Gamma1: Welcome to your forum! 


if you have the the USB 2.0 attached to the ports directly on the outside of the PC depending on the age & wear & tearto the port it could be that the connections from the port to the motherboard could be coming apart causing the "peek-a-boo" problem 


the 3.0 could also be affected by the intermittent power problem that's in the 1st paragraph or the power supply to the external one could be starting to give it up itself maybe you should consider replacing both with a powered hub with at least 4 ports then affix both to the ports on the hub finally attacting the hub itself to a functional port on the computer itself then observe if that solves this vextation 


I've had both problems bedeviling my 7 yr. old Pavilion 410y ultimately that's how I solved it for my happiness

if not or if there's anything else you're pondering please don't hesitate to seek us out

that's why we're here 24/7/365.25

good luck in this endeavor


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