C++ compiler error message not understood

I bought my first C++ compiler yesterday (MS Visual C++ professional edition). I am having trouble getting even the most basic programs to compile, build, and execute. I've had success with computers at work doing this, but no luck at home which makes me think maybe my settings are not correct? Please help meeeee!!!!
Here is the code I tried to compile:

#include <stdio.h>
main()
{
printf("Hello World!\n");
return 0;
}

Here is the error message that I am getting:


--------------------Configuration: test4 - Win32 Debug--------------------
Compiling...
test4.cpp
fatal error C1900: Il mismatch between 'P1' version '19991026' and 'P2' version '19970710'
Error executing cl.exe.

test4.exe - 1 error(s), 0 warning(s)