wont let me join...

well i was bored on reach so i was snooping round on the um…file browser and stuff then i saw that waypoint thing where you have to download it so i clicked download but it wont let me and now everytime i sign in it says ‘download failed’ and im like urghhh its really annoying. and whenever i insert halo 4 or 3 it makes me do an update so i wait for like half an hour and it doesnt do ANYTHING so i click cancel and it just freezes…
does anyone know what is wrong and why cant i download it because it really bugs me that i cant go on it, also it wont let me join games with friends either sometimes is that the stupid xbox or does it just happen sometimes?
thank you in advance:)

Problem with connection would be my first guess. Next would be issues with your HDD, memory space.