I want to know why my usb devices do not work at all. All my usb devices can not be mounted to my system. Only my mp3 player which need battery in it can be mounted to my system. Please tell me how to mount my usb devices like flash memory to my computer? Thanks

It may depend on your kernel. I have 2.6.13. There were some changes made in the 2.6 kernels. maybe you should google a bit if you just switched kernels. Concerning usb, I have these options in my fstab:

/dev/sda1 /mnt/flash vfat user,noauto,umask=0 0 0
usbfs /proc/bus/usb usbfs devgid=14,devmode=0660 0 0

It may be that you need some extra kernel modules. What do you see when you run lsusb? does your kernel have the correct usb options? I recall you have three different usb connections: ohci uhci and something else. do you have them in your kernel? also make sure that the filesystem on your device is supported by your kernel. In my case that was vfat.

Only a device with builtin power works? Strange... When you connect a device, try a flashdrive, does anything appear in dmesg? Connect a flashdrive, run dmesg at a terminal and see if it detects the device and assigns a device node such as sda1. If so it can be mounted by mounting /dev/sda1 to a directory.

What picobyte suggests is good, too. Look in your kernel's config and see what usb options are enabled as either * or M (builtin or module). USB 1.0 and 1.1 require ohci and 2.0 requires uhci. ehci is not as common.

What distro and version # are you using?'
When I used Mepis 3.3, none of my USB drives were recognized or mounted when I plugged them in. Once I switched to 3.3.1, they were recognized and mounted automatically.

Ubuntu 5.04 and 5.10 also do this. I would suspect the most recent version of the major "newbie" distros would all do this (Fedora, Mandriva, Xandros, SuSE, etc.).

the version of my kernel is 2.6.11. the portable harddisk can be mounted.but the flash disk cannot.

thank all the repliers for helping me. your advices are very valueable for me.