I can not login

i noticed that no one else had answered your question yet. not sure if i can help, but i'll try anyways.

wikipedia says: A segmentation fault occurs when a program attempts to access a memory location that it is not allowed to access, or attempts to access a memory location in a way that is not allowed

you should be able to reset your password in recovery mode. if your getting a segfault, maybe you can try to remove a stick or two of memory and try again. if it doesnt work, swap the ram with the ones you took out. basically i want to see if any memory modules you have are bad? Depending on your motherboard, ram may need to be installed in singles, pairs, or three at a time with the new i7 core.

alternatively you can boot off a liveCD and run the memtest but it takes a while to complete.

Can you log in at tty1? At the login screen press "ctrl+alt+F1" and try to log in there. If you can get in, good. It may be an x issue, or an issue with GDM. If you cannot log in there you need to verify the proper login credentials.

This will get you the active user name, and allow you to reset your password without having to even boot into the "recovery mode":

<b>Step One. Gain root (or administrative) access.</b>

This step can be used to gain root access to any computer running Ubuntu that you have physical access to.

   1. Power up the computer, and watch it load the BIOS
   2. When it says "grub loading..." hit the "esc" button to get into the "grub menu".
   3. hit the "e" button to go into edit mode.
   4. Highlight the line that begins "Ubuntu, KERNEL......." and hit "e" for edit again.
   5. At the end of this line add this

                             rw init=/bin/bash

and then press "enter".
   6. Press "b" for boot.
   7. You will boot into a "root shell". This means you have administrative powers in the system now. You should see something like this

                           root@some-computer:~$

and nothing else.

<b>Step Two. Recover the user name.</b>

This is pretty straight forward. All you need to do is enter in the following code and press enter.

                          grep x:1000 /etc/passwd | cut -d: -f1

make sure you do it exactly as you see here, it is case sensitive. This should give you the name, let's say it gave you the name bob...write it down.

<b>Step Three. Reset the Password</b>

Again, this is pretty straight forward. Just enter in

 passwd bob

and press enter. <b>Make sure you replace "bob" with whatever you got as a response in step 2.</b> It will ask you for a new password, and then ask you to enter it in again to confirm. Now you have reset the password for the user name you received in Step Two. Congrats, if you followed and all went well, you now have the active user name and password. Now you can reboot, and log in as normal.

If what you are experiencing is some weird password/security issue, this will definitely give you the proper login credentials. If you continue to receive segmentation faults, I would download an Ubuntu cd and run the memory test. If there is a bad piece of ram there, it will usually (or has for me) spit out errors fairly early on. The test does run for quite a while, but if it shows you errors right away, then there is no need to let it run all of the way through.

If the memory test passes, and you get the correct login info and still no dice with the graphical log in, I don't know what to suggest but a reinstall. If you do reinstall and still get the same errors, then you have a hardware failure, perhaps even a bad video card?

Thanks for the help. I did a memory test and all passed. I tried the all that Joshua recommended twice. Thanks Joshua for the detail. My hard drive has another partition on it that had Linspire loaded on it so I Installed Kubuntu on it and I can get to all my files. So when I finish transferring all the stuff I will reload ubuntu.

Thanks