Installation problem D-Tools 3.47

[WilliamWallace]

Operating System: Windows XP service pack 1
Burning Software: Nero 6, alcohol 120% clone cd
Anti-virus Software: nod32
DAEMON Tools Version: 3.47

when i run the installer after a while installation stop..

i've made the log of the installation..

near the end of the .txt there's a line saying installation stopped because of this:

Property(C): VSDVERSIONMSG = Unable to install because a newer version of this product is already installed.

but i have no version installed!!!help me..thanks!

[WilliamWallace]

now i've tryed to install dtools 3.46 and they work great..

what kind of problem can be!??!thanks!