I have a big problem playing demos because when i run them ( both usinf DD player and by typing "demo1" in soldat) it turns on and then a black parachutes appear everywhere on the wachting map and solda crashes with soldat.exe error...In the past my demos worked well so i dont know whats happened..:|

Have you tried reinstalling Soldat?

Make a backup of your demo, uninstall Soldat, delete the Soldat folder, restart, reinstall Soldat, and try playing your demo again.

try change folowing player when black parachutes soon come. After this you can see normal demo.