I still want to change the indentation. I added the code (setq-default
tab-width 4 indent-tabs-mode t) to the file (\AppData\Roaming\.emacs in my
user folder in windows) as you said, but it doesn't work. What can be wrong?
And why can't I change it through Options->Customize Emacs->Top-level
Customization Group? To me it seems like something is wrong if nothing of
this works. What does it sound like to you?
I also tried pasting the code in my .cpp file, and evaluating it by placing
the cursor after it and pressing C-x C-e (now I understand how C-x C-e works
by the way). The minibar then displayed t; I guess that should be right. It
still didn't work after that; the indentation was two spaces, just as
before. The file I'm editing is a C++ file; I guess the indentation should
work for those files as well.