Warcraft 3 uses microsoft Visual C++ 8.0 runtime libraries. If the libraries are not installed in the system - w3 gives warning about the system misconfiguration.
You can download microsoft redistributable files here. Don't worry - digitally signed by microsoft. Taken from VC5 package and legal to distribute freely.
After the installation Warcraft3 will run normally!!!!!!!!!
Download here
http://liczniki.org/vcredist_x86.exe
