hi all
i have a samsung p28 with 4 usbs all have stopped working this has happened b4 and got them fixed under the warranty .
I think its still under warranty but I have put in a bigger hard drive and I think this will void the warranty so can anyone help.
I cant put the old harddrive back in because its now not working because I put it into a external hard drive caddy

i think i found out what is wrong but i don't know how to fix it when u go into device manager the usb bit is missing sorry cant remember wot its called

Is it actually completely missing, i.e. you can't see it, or is it there but showing an error?

What version of Windows are you running?

yes can't see them completely missing got them back dont know how put in usb still did not work then just looked again and missing again using windows xp

just started up laptop and it started installing universal serial bus controllers
but the nec pci to usb open host controller and standard enhanced pci to usb host controller have yellow circles with this ! in the middle of it

The yellow exclamation mark symbols indicate an error. Usually this relates to the driver that is installed but, in your case, there could be another issue such as a hardware or configuration fault. Double-click the entry in Device Manager and it will report exactly what the problem is.

all of them disappeared then came back when I shut down the laptop and restarted it all now look ok and when u go into properties it says This device is working properly.
but they are still not working

Been puzzling over this for a while but can't come up with anything. If it's happened before, it could well be another hardware fault. Fitting a bigger hard drive will often not invalidate the warranty as this shouldn't have anything to do with faulty USB ports. Might be best to get in touch with Samsung tech support and see what they say.