i just installed debian lenny, very basic install so far.
apt-get update returns this error:
Failed to fetch http://security.debian.org/dists/len...86/Packages.gz Hash Sum mismatch

E: Some index files failed to download, they have been ignored, or old ones used instead.

i googled and tried:

apt-get update -o Acquire::http::No-Cache=True
apt-get update -o Acquire::BrokenProxy=true
apt-get update -o Debug::Acquire::http=true

but same.
deleted files in /var/lib/apt/lists and ./partial
but again, same error.

i have another lenny machine on same network, same configuration,
--
less /etc/apt/sources.list

deb http://ftp.monash.edu.au/pub/linux/debian/ lenny main non-free contrib
#deb-src http://ftp.monash.edu.au/pub/linux/debian/ lenny main non-free contrib

deb http://security.debian.org/ lenny/updates main contrib non-free
#deb-src http://security.debian.org/ lenny/updates main contrib non-free

#lame darkice and such
deb http://debian-multimedia.org/ lenny main

--
any ideas?

Out of curiosity, are they both the same versions of apt?

apt -version

yes, the versions are identical.
apt-get -version (bad box)
apt 0.7.20.2 for i386 compiled on Apr 20 2009 21:52:39
...
and (good box)
apt 0.7.20.2 for i386 compiled on Apr 20 2009 21:52:39
...

i WAS inclined to reinstall lenny. (i found many references to that problem via google, but no solution.)

i just ran apt-get update again, and all is fine. caching problem?

anyway, though not solved, the problem is gone!
thanks

try

or