W: Failed to fetch bzip2:/var/lib/apt/lists/partial/ftp.tw.debian.org_debian_dists_experimental_main_i18n_Translation-en Hash Sum mismatch W: Failed to fetch bzip2:/var/lib/apt/lists/partial/ftp.tw.debian.org_debian_dists_unstable_main_i18n_Translation-en Hash Sum mismatch E: Some index files failed to download. They have been ignored, or old ones used instead.