当我尝试在 11.10 上更新软件时，出现以下错误：
W: GPG error: http://repository.akirad.net akirad-oneiric InRelease: File /var/lib/apt/lists/partial/repository.akirad.net_dists_akirad-oneiric_InRelease doesn't start with a clearsigned message
W: Failed to fetch gzip:/var/lib/apt/lists/partial/repository.akirad.net_dists_akirad-oneiric_main_binary-i386_Packages Encountered a section with no Package: header
W: Failed to fetch http://repository.akirad.net/dists/akirad-oneiric/main/i18n/Index No Hash entry in Release file /var/lib/apt/lists/partial/repository.akirad.net_dists_akirad-oneiric_main_i18n_Index
E: Some index files failed to download. They have been ignored, or old ones used instead.
通过 GUI 更新软件也会给我关于下载包的错误，但它们不那么冗长。
我在最新版本的 Ubuntu 中执行更新从来没有遇到任何问题。
我需要做什么来修复这个错误？