Can't update

I don’t have an internet connection in my computer. So I download avast updates
from avast’s website in a cyber cafe. Then I bring them home on my thumb drive.
But yesterday at home when I tried to install a VPS update this error came up:

Can’t install VPS update. Please, report following errorcodes:
Ver:4.8.1229
SI: 0x00000002
ST: 0xFFFFFFFF
LE: 0x00000000

I’ve updated my avast database/program in this way many times before but never
had any kind of problems. Please help me.

Download the update here: http://files.avast.com/iavs4pro/vpsupd.exe

Or copy 400.vps and clnr0.dll files from an updated avast installation to a USB stick and transfer them to the \Data folder of the off-line computer (having disabled the avast self-defence module first).