C Code: Comparison with an int fails and I have no idea why

I'm dealing with a strange problem and I'm not the best C Programmer on earth, so be gentle with me! :)

The thing is: I'm trying to compare a value based on a volatile unsigned int Pointer. The Basic Code looks like this:

    // *error_data is a volatile unsigned int Pointer
    int code = (int) *error_data;
    printf("Errorcode: %d\n", code); // prints 400 and is definitely 400!!!
    if (code == 400)    // here the comparison fails totally
    {
       printf("Test.\n"); // I'm never getting this output
    }
    else
    {
       printf("WHY???\n"); // I'm always getting this path of the if statement
    }

Does somebody know what's the issue? I'm working on this Problem since yesterday and broke down the example to this and I have no answer why this happens. It's really weird.