Seems alotta ppl are having this problem:
After downloading and installing the 900MB+ 9DVN file, NDLAUNCHER.EXE is detected as a virus. NOD32(antivirus) would not let me continue with step, unless i disabled it... when the game is installed, for some ppl NDLAUNCHER.exe might be blocked and deleted by the antivirus... for me it didnt (kinda weird yes i know) but a few days later some files in the %TEMP% directory were suspected of being trojans :S
so try 9D VN at your own risk, im runnin it fine and none of my accounts have been lost
so once again
1. RIGHT CLICK your antivirus and disable it
2. Run the installer
3. Enable your antivirus
4. run the game. if it doesnt, then the file still got deleted, and u gotta keep ur av off (not recommended) while playing 9dvn