#8 I am puzzled by the message "400 Bad Request....."

[yanqian]

Thank you for developing the program.
I connect to internet via ISA server, when I was in Windows XP, IE and Firefox work well, but in Linux,I couldn't download file under console,such as apt-get update、wget，then I found this program few month ago,it worked well for a time.

but recently I got the message below when I run apt-get update:
400 Bad Request ( The data is invalid. )

I am puzzled, why I got the message?
because ISA server changed settings? I don't know.