Disappearing Incoming connections

Hi Brilliants,
I hav a problem with my Incoming connections in my xp.we use dial up for updating the client n for remote access– VNC.
my problem is that when I am trying to accss a remote pc which I hav already configured myself,is not answering.
I went to the client to check the problem and there is no incoming connections there.
as I have started to reconfigure the incoming connections,there is no need of giving more effort.only next–next and next is enough.
when I am restarting, this problem happens again.
If anybody knows what to do,plz tel me.
that will be a great help,bcause,we have more than 500 clients @ differnt locations.
thanking you in advance.

SujeshPJayaram
MCM Middle East
00971509491636