Help Problems updating Sensation XE


I just got my HTC Sensation XE 6 days ago and yesterday I got a SD card for the phone and I'm trying to update the phone to the 3.33.401.6 software which is 60.61MB and every time I try nothing seems to be happening.

When I try to install the update from the hboot this message comes up:
E:Error in /sdcard/Download/
(Status 7)
Installation aborted.

When I enable signature verification it starts installing to about 25-30% of the bar and then this message comes up:
E:failed to verify whole-file signature
E:signature verification failed
Installation aborted.

I've tried several things and to try and fix the problem and none of them have worked.

What's happening? Why does this happen? What can I do to fix this?