The wireless USB keyboard stops working when I connect a USB hard drive. I also tried to connect a non wireless USB mouse together with the USB disk and the mouse stopped working.
I'm running raspbian as OS. The disk was first formated as ntfs, but I have also tried changing the file system to ext4.
The USB disk works well on my Ubuntu laptop.
So is this power related or can something else cause the problem? I'm using the power adapter from an HTC mobile phone.