Recently I installed Ubuntu 12.04 on my USB flash drive and loaded it on my laptop. It was good and I was able to work. My keyboard and mouse was working fine. I liked the Ubuntu and installed on the hard drive of the laptop. Installation was smooth. When I booted with Ubuntu in laptop it was not at all detecting mouse and keyboard in my laptop. However it was detecting usb keyboard and usb mouse when I attached to it. However it was able to detect keyboard in the grub loader stage.
How cannot it detect keyboard and mouse when USB ubuntu installation was detecting keyboard and mouse?
What is the use of an operating system with so many features, if it is not able to detect keyboard and mouse?
I searched in the google and there is no convincing answer. Is that a permanent bug in the ubuntu?