error message after log in..

[Howard Protheroe]

hello,

I am hoping somebody can help with some small but very irritating problems.

1. I have managed to rename my computer to X1-6-00-04-e2-a3-5f while trying
to install stuff and don't know how to change it back to something more
simple.

2. When I log in I get an error message :

Could not look up internet address for X1-6-00-04-e2-a3-5f
This will prevent the GNOME from operating correctly.
It may be possible to correct the problem by adding X1-6-00-04-e2-a3-5f to
the file /etc/hosts

I have limited knowledge of Linux and I am running redhat 2.4.20-31.9.

Any help is much appreciated.

Howard