> I have two windows 95 computers, Computer A has vsocks light proxi and
> Computer B that has computer A as gateway. Both are on the same window
> s95 LAN and within the same group, Computer A ip:152.99.20.1 and
> Computer B ip:152.99.20.55, when I try to stablish a vnc session from
> computer B to A that message appears, I tried with other machines and
> all work fine and all connect to computer A, what could be wrong?  
 
By default, WinVNC checks all incoming connections to see whether or not
they originated from the same machine.  If they did then they are
rejected.  The check is done on an IP address basis, which is probably why
this problem is arising.
 
You can disable the check using the AllowLoopback registry option for
WinVNC.