The 1671 bytes is the version information it get.
It looks like it never even start to download the actual update file.
Why it does not do that is impossible to say. Some AV, Corporate firewalls, ISP or other might block the request.
You can try to start MultiUpdate manually and then go into settings and there you can check
the option "Use IE User Agent" this will trick some to let the request through. You can also try "Use WinInet for download".
And if none of that work you can download the update file manually (You see the link to the file in the window.. Just copy that. )
When you got the update file you then go to the settings page in MultiUpdate and check "Update from a MultiUpdate file" and then select the downloaded update file.
Then you start the update and it will do the update from that file.
