"Cannot open display" or XDMCP problem ?

[Robert, Francois]

I am sincerely sorry to report that none of the suggestion from Clive and
Suhaib did not succeed :

> Can you try adding -ac to the XWin command line
> instead of using xhost (temporarily..)

> XWin95 :0 -from 129.227.62.61  -query 129.227.62.246  && xhost + &

So, to sum up the situation, here are the various stuff I have tried so far,
to no avail :  

DHCP vs. fixed IP 

-from <my ip> vs. nothing 

-ac vs. & host + 

XWin95 ... && xhosts + & vs.  
XWin95 .... & xhosts + & 

export OS="" vs. export OS=" " vs. no OS environnement variable

XWin95 :0 ...

Clive buttler suggested a possible explanation in :
http://sources.redhat.com/ml/cygwin-xfree/2001-q2/msg00325.html
and in :
http://sources.redhat.com/ml/cygwin-xfree/2001-q2/msg00328.html
But none of them seem convincing, since -ac still does not allow XDMCP to
work. So I am back at square one (well, almost...)

Any other suggestion is thus still welcome...

François