I can't login to Crunchbang Linux

Question

I rebooted my VM and now I can't login. It gives me the following error:

Your session only lasted less than 10 seconds. If you have not logged out yourself, this could mean that there is some installation problem or that you may be out of diskspace. Try logging in with one of the failsafe sessions to see if you fix this problem.

View details (!/.xsession-errors file)

/etc/gdm/Xsession: Beginning session setup...
mkdtemp: private socket dir: Permission denied

When changing the session to failsafe gnome it gives me Could not find the GNOME installation, will try running the "Failsafe xterm" session. And when trying failsafe terminal I get Cannot find "xterm" to start a failsafe session.

I had not rebooted my VM in a while; I can't think of something that would cause this. But how do I fix it?

Edit: The output of stat /tmp:

  File: `/tmp`
  Size: 4096        Blocks: 8        IO Block: 4096   directory
Device: 801h/2049d    Inode: 131238    Links: 13
Access: (0755/drwxr-xr-x) Uid: (    0/    root)  Gid: (    0/    root)
Access: 2012-02-15 06:18:42.360913478 -0700
Modify: 2012-02-16 19:17:01.514555114 -0700
Change: 2012-02-16 19:17:01.514555114 -0700

Answer 1

If you have a vSphere client set up on a Windows machine, you can access a VMware ESXi server host by using it. It gives you access to the system console and so on, although you should be able to log into the system with one of @Gilles recommendations. If not, you should be able to log in through the system console, or by booting from an ISO (by changing the VM properties and booting from an ISO file) and performing a recovery if you must.

Answer 2

/tmp is not sticky, nor world-writeable. It should be 1777/drwxrwxrwt. The sticky bit allows every user to create a file in the directory, and modify or destroy the files it owns.