My USB Ports have 'sort of' stopped working!

[BrianJ33]

Hi All,

I have a HP M7733fr desktop about 4 years old, all was well until a couple of days ago when all my USB ports 'sort of' stopped working.

 I say 'sort of' because if I boot up the PC with something plugged into any USB port then that  item will work ok. If I unplug it and plug it straight back in, it no longer functions and nothing happens on the PC. Also since then, the little LED on the built in multicard reader stays illuminated all the time with no card plugged in (the card reader of course doesn't work as it is also one of the USB ports). If I plug in a USB memory stick to any port, the LED illuminates on the stick, but nothing else happens and it is not visible in Windows Explorer.

Things I have tried already that have made no difference:

Restored System back to the past when all was working.

Uninstalled all USB Universal Host Controllers and USB Root Hubs both individually and together via Device Manager then robooted PC (tried this  several times) - the drivers all get reloaded and they all say they are functioning correctly.

Unplugged the built in card reader from the motherboard in case it had a fault

Enabled and disabled legacy USB support in the Bios - either position makes no difference.

So I am at a loss as to what to do next, the USB ports do work but only if something is plugged in at boot up and left in place..............anyone experienced this or  have any suggestions  help please.........

thanks