GCC/C::B problem (A tragedy in 2 Acts)

[atropos]

The other day, I was able to successfully download and install gcc 4.7.1 on my winXP laptop. PATH variable was set,

g++ --version

at the command prompt yielded the expected result, and Code Blocks detected the compiler. I tested things out with a little program:

#include <iostream>
#include <vector>

int main()
{
    using std::cout;
    using std::endl;

    cout << "Hello World!" << endl;
    cout << "\nTesting C++11 compatability\n" << endl;

    std::vector<int> vec = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
    for(auto pos = vec.begin(); pos != vec.end(); ++pos)
        cout << *pos << endl;

    for(const auto& elem : vec)
        cout << elem << endl;

    return 0;
}

and all was well.

Today, I wanted to install the same thing on my windows 7 laptop, but I had to use an offline installation. After downloading the executable from
http://nuwen.net/mingw.html and running it, I once again set the PATH variable then checked the current version at the command prompt. Everything checked out. I made all neccessary changes in the Code Blocks toolchain and tested with the same program. C::B responded with
<"test - debug" uses an invalid compiler. Probably a problem in the toolchain settings? Skipping...>

What confuses me is that all the settings are identical for both laptops, yet it just doesn't work on one of them?

I've checked and rechecked a thousand different things and nothing works. I'm at my wit's end. If anyone knows what's wrong or can help me, it will be greatly apprieciated.