sounds to me like an issue with your dual monitor app rather than GV.

try UltraMon i use it for 2 monitors w/out problems/

software is geovision 6.1.0.0
dvr card: pc based vki-600

my goal is to use multicam on monitor 1 and do my work on monitor 2

using dmpos.exe multicam software is running on monitor 1 and all cameras are displayed correctly, but when i try to open multicam on fullscreen then multicam sofware go away from monitor 1 and on monitor 2 i see Black clean fullscreen.

question:
why i cannot make fullscreen on monitor 1 ?

What type of geovision card is a ' vki-600'?

Not heard of that one before.

does it full screen on other monitors? i've seen directdraw overlay or de-interlace when disabled cause this problem.........your problem allow may be whatever type of card that is