May seem like a stupid question, but I just can't figure it out.
They just mount for me on the desktop. If I insert a USB Thumb Drive, it mounts, and if I insert a CD, it mounts.
For me they just worked.
There's a mount menu on the Deskbar, you can mount USB devices from there and modify Haiku's mounting behavior.
I get a "general systems error" when I try to mount a CD/DVD, and my USB drives won't even show up.
Please also help with my WiFi problem in the other thread! I am an internet-24/7 person. If I can't get internet I probably won't use Haiku too much.
What is your hardware setup?
concerning your USB drives (I suppose you are using external HD and CD/DVD):
try changing the USB port - sometimes the port has not enough current capacity t