I am not able to log in

[yoreei]

I installed fedora a few hours ago. But when I rebooted (for the first time) and tried logging in, the computer freezes for a second, shows a blank black screen and then returns me to the login menu. I can, however, login when I choose recovery mode from grub. I even tried changing the password, making another user which all worked while I was in recovery mode but I still can't log in when booting as normal. The new user account that I created is shown on the menu but when I try logging in through it I am again returned to the login menu.
I use Fedora 17 x64 LXDE.

I also tried

startx lxde

while I was in recovery mode but the following error occured


This might be a silly question as I am new to Fedora and Linux but is this normal or is it related to the login problem (perhaps lxde can't start because of the second problem so it returns me to the login screen?)

Thank you in advance!

---------- Post added at 08:48 PM ---------- Previous post was at 08:35 PM ----------

Hi again. do you guys think it is possible that an overfilled /tmp is causing this problem? I am suggesting this because I also had another problem before this one happed that SEA thought might be because of an overfilled /tmp

[Seve]

Frankly, you might be best to just reinstall F17 and go from there.

[stevea]

No your situation is not typical.
Don't reinstall - that's a shotgun approach,

For a start try ...
startx /usr/bin/lxsession
to get an initial xsession started.
If that fails youll get some useful error messages.

How did you insall F17 ? From a CD or the DVD ?
How did you attempt to configure lxde as the default desktop ?
Is gdm still installed ?
Are their error messages in ~/.xsession-errors ?
In /var/log/Xorg.0.log

[yoreei]

startx /usr/bin/lxsession has a similar output as startx lxde on the picture above but instead it doesn't say anything about xterm and pops the "connection to X server lost" straight away.
The ~/.xsession-errors is empty and var/log/Xorg.0.log is a veeery long list of things I barely understand that randomly says something about missing drivers.
What is even more strange is that when I tried startx lxde today the output was completely different! Actually, the only thing that happened was that the screen went black and the button on the monitor started blinking as if there was no signal from the computer. I tried moving the mouse, bashing the keyboard in order to wake it up but nothing happened.
I installed Fedora LXDE x64 bit from a DVD. I downloaded the iso from the fedora website with lxde already configured (I was asked with which DE I wanted Fedora and I chose LXDE because I really like it). I don't have gde, I never did.