This has only just Started happening and the green light is on when i reboot the logitech profiler states it cannot find any devices, and i should plug it in a power supply even thought it Calibration while window starts

If any 1 can halp ill be happy

ty austin

Just plug it into a different USB port if its on a hub connect it on a USB port on the pc not the hub and lastly if that doesn't work try to un-install and re-install the drivers plus the profiler

done that stil doing it

If the G25 isn't dead (sticking it another PC would confirm this, and that's what I'd do 1st) then the USB enumerator could be screwed - the symptom of this is either nothing happens when you connect the G25 (i.e. no usb 'sound' when it's plugged/unplugged) or it detects something then doesn't install the actual device.
If this is the case you can try safe-mode, disconnect the G25 1st then remove any old/duplicate USB devices (edit - including any G25's) in device manager and re-boot and reconnect. If that doesn't work it'd be a registry job which you can probably google for.