Cant run more than 1 USB device.

Hi,

I have WinXP machine (not the one you see on the bottom) in very good condition. Newer PSU with sufficient wattage, yet I cant run more that 1 USB device (no hubs). I have my printer connected in, but if I plug in as flash drive, scanner, or a hard drive none come as "recognized." If I kick out the printer I can work the other one and only one. The USB ports are all fine and so are the devices.

What do I do?

I wonder if it's actually one of the USB devices that you are always trying (printer?) can you try two other USB devices.

Also go to device manager; right click on the USB devices and check for updates online.

Are these all bus powered devices or do they have their own power adaptors?

I gather:

Printer -Yes
Scanner - Yes
Flash Drive - No

Not sure what is doing it myself though
Just trial and error at this stage, try this try that

I can work only one device at a time (printer or not). In any combination only one works and that is the one that is plunged in first. Printer and HDD have their own power supply, flash drive and scanner do not, however non of them work together in any combo even if both have the Power elsewhere.

Sounds like a USB driver hasn't been installed. Have you checked in Device Manager? Assuming your XP is SP2 you'll have the USB driver on board ready to go.

I should've said USB 2.0 driver.

All the drivers are fine. Front and back. I can work one device on any port on the PC and one device only (even runs 2.0 lol ). It must be something else.

And you know come to think of it my PC at work has the same problem. I have (had) USB printer hooked up and when I plugged in my flash drive...nothing. Unplug the printer and it works again.

Could I be the unknown variable I am looking for?

Must be either your flash drive hurting USB's on computers
Or your flash drive contains a bug, which is affecting computers

In both cases the damage is done even after removing it.

By the way you are following safe removal practice, not just pulling out the stick, I take it.

Like I have said:

It is not the flash drive solo. any other USB device.
And I have learned about the save removal procedure hard way some time ago, if you know what I mean...

No I mean by using your flash drive on the computer, now they are faulty, even without it.
ie it's the only common denominator here.

flash drive is just an example of USB device that is not working. Take it out of the equation and you still have HDD, scanner, and printer. And I still can work only one at a time

Even on another computer, that has had your flash drive plugged into?
If so then I can only think the flash drive has caused issues



Sorry must leave for awhile, be back 10 hrs from now !

it is not the devices that cause the problem. I have 3 other PC's and they can all run all the devices at once and then some...

As a basic troubleshooting step go to the Device Manager and uninstall all

USB controllers,then shutdown the computer and attach two USB devices then restart

the computer.

The only other thing i can think of is some issue with drive letters.

If you have a lot of network shares that can use up drive letters,maybe ?

I will try that...

I should still have about 15 free letters.

I wonder if this some type of trojan, that both computers have.

Possible the original trojan is now not on the USB drive, but still in Windows.

Or it is a specific program only running on the home and work that is causing it.

Seems strange that 2 computers have the same issue, with a unique fault.

If the problem would be on my PC only I would be inclined to Trojan, but at work we use hefty security protocols, and I don't thing Trojan would slip by undetected for such a long time. Also The work PC was re-imaged less than 4 months ago and the problem was there since the beginning.
In addition I use the USB drive on all my 4 PC's at home and only one has the problem and none others have detected any viruses lately.

At this point I am very inclined to point to my PC power supply. That seems to me most logical explanation at this point in both cases. PC at work is few years old and so is my PC. Both run long periods of time and PSU's were not exchanged ever.

I will explore that possibility once I have time.

If you have any more ideas keep'em coming...

Power supply is a good idea

Everything should work via a usb hub if your power supply is the problem.