So you updated using yum, and lo and behold yum is no longer working. An attempt to use yum gives you the following:
There was a problem importing one of the Python modules
required to run yum. The error leading to this problem was:
No module named cElementTree
Please install a package which provides this module, or
verify that the module is installed correctly.
It's possible that the above module doesn't match the
current version of Python, which is:
2.4.3 (#1, Jul 27 2009, 17:57:39)
[GCC 4.1.2 20080704 (Red Hat 4.1.2-44)]
If you cannot solve this problem yourself, please go to
the yum faq at:
I had this error on a CentOS5 VPS. Now, the fix for this is simple enough. It involves removal of some packages, then re-installing those packages we removed.
rpm -e yum yum-fastestmirror python-urlgrabber python-sqlite python-elementtree
rpm -i yum-3.2.22-20.el5.centos.noarch.rpm yum-fastestmirror-1.1.16-13.el5.centos.noarch.rpm python-urlgrabber-3.1.0-5.el5.noarch.rpm python-sqlite-1.1.7-1.2.1.i386.rpm python-elementtree-1.2.6-5.i386.rpm
Of course bear in mind the architecture and versions (depends when you are reading this post!) of the files.
This should get you up and running again.