I also had this problem and I found that if I just finish typing the shortcut it would create the symbol I wanted in the url bar (I'm using Chrome). I just copied it from there and went back a page for the longest time.
It turns out that for some reason I hit the number lock key on my keyboard (no idea how) but without number lock on it would redirect me to the about:blank page and with number lock on it would just make the symbol.
Alt+home brings you to your home page and 7 and home are on the same key for me.
I don't know if this is your problem but it was mine so hopefully this information will help.