GDM problem

[Piers Kittel <edinfo-list biased org>]

Hello all

Am having a problem with GDM.  I installed it before and it worked just 
fine.  Then suddenly (well it probably was something I did) one day, GDM 
wouldnt work.  The computer would boot up, and start X just fine, see 
the grey/white background but it would then "switch" screens and see 
black for a couple seconds and a message would come up:

"There already appears to be an X server running on display :0.  Should 
I try another display number?  If you answer no, I will attempt to start 
the server on :0 again (You can change consoles by pressing Crtl-Alt 
plus a function key, such as Crtl-Alt-F7 to go to console 7.  X Servers 
usually run on consoles 7 and higher)"

When I press no, the same thing happens again.  If I press yes, the same 
thing happens again, but the error message will now show :1 instead of 
:0.  Pressing Crtl-Alt-F7 would show the grey background and the cross 
mouse pointer.

What am I doing wrong here?

Thanks very much for your help in advance

Cheers - Piers