fresh natty install i386 desktop. I get this errors:

Code:
$ sudo apt-get update
Ign http://extras.ubuntu.com natty InRelease
Ign http://archive.ubuntu.com natty InRelease
Ign http://archive.ubuntu.com natty-updates InRelease
Ign http://archive.ubuntu.com natty-security InRelease
Hit http://extras.ubuntu.com natty Release.gpg
Hit http://extras.ubuntu.com natty Release
Err http://archive.ubuntu.com natty Release.gpg
  Bad header line [IP: 91.189.92.171 80]
Ign http://archive.ubuntu.com natty-updates Release.gpg
Hit http://extras.ubuntu.com natty/main Sources
Err http://archive.ubuntu.com natty-security Release.gpg
  Bad header line [IP: 91.189.92.171 80]
Ign http://archive.ubuntu.com natty Release
Ign http://archive.ubuntu.com natty-updates Release
Hit http://extras.ubuntu.com natty/main i386 Packages
Ign http://extras.ubuntu.com natty/main TranslationIndex
Get:1 http://archive.ubuntu.com natty-security Release [31,4 kB]
Err http://extras.ubuntu.com natty/main Translation-en_US
  Bad header line
Err http://extras.ubuntu.com natty/main Translation-en   
  Bad header line
Get:2 http://archive.ubuntu.com natty-security Release [31,4 kB]                                                                                             
Ign http://archive.ubuntu.com natty/main Sources/DiffIndex
Ign http://archive.ubuntu.com natty/restricted Sources/DiffIndex
Ign http://archive.ubuntu.com natty/universe Sources/DiffIndex
Ign http://archive.ubuntu.com natty/multiverse Sources/DiffIndex
Ign http://archive.ubuntu.com natty/main i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty/restricted i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty/universe i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty/multiverse i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty/main TranslationIndex
Ign http://extras.ubuntu.com natty/main Translation-es                                                                                                       
Ign http://archive.ubuntu.com natty/multiverse TranslationIndex                                                                                              
Ign http://archive.ubuntu.com natty/restricted TranslationIndex
Ign http://archive.ubuntu.com natty/universe TranslationIndex
Ign http://archive.ubuntu.com natty-updates/main Sources/DiffIndex
Ign http://archive.ubuntu.com natty-updates/restricted Sources/DiffIndex
Ign http://archive.ubuntu.com natty-updates/universe Sources/DiffIndex
Ign http://archive.ubuntu.com natty-updates/multiverse Sources/DiffIndex
Ign http://archive.ubuntu.com natty-updates/main i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty-updates/restricted i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty-updates/universe i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty-updates/multiverse i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty-updates/main TranslationIndex
Ign http://archive.ubuntu.com natty-updates/multiverse TranslationIndex
Ign http://archive.ubuntu.com natty-updates/restricted TranslationIndex
Ign http://archive.ubuntu.com natty-updates/universe TranslationIndex
Ign http://archive.ubuntu.com natty-security/main Sources/DiffIndex
Ign http://archive.ubuntu.com natty-security/restricted Sources/DiffIndex
Ign http://archive.ubuntu.com natty-security/universe Sources/DiffIndex
Ign http://archive.ubuntu.com natty-security/multiverse Sources/DiffIndex
Ign http://archive.ubuntu.com natty-security/main i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty-security/restricted i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty-security/universe i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty-security/multiverse i386 Packages/DiffIndex
Ign http://archive.ubuntu.com natty-security/main TranslationIndex
Ign http://archive.ubuntu.com natty-security/multiverse TranslationIndex
Ign http://archive.ubuntu.com natty-security/restricted TranslationIndex
Ign http://archive.ubuntu.com natty-security/universe TranslationIndex
Hit http://archive.ubuntu.com natty/main Sources
Hit http://archive.ubuntu.com natty/restricted Sources
Hit http://archive.ubuntu.com natty/universe Sources
Hit http://archive.ubuntu.com natty/multiverse Sources
Hit http://archive.ubuntu.com natty/main i386 Packages
Hit http://archive.ubuntu.com natty/restricted i386 Packages
Hit http://archive.ubuntu.com natty/universe i386 Packages
Hit http://archive.ubuntu.com natty/multiverse i386 Packages
Hit http://archive.ubuntu.com natty/main Translation-es
Hit http://archive.ubuntu.com natty/multiverse Translation-es
Hit http://archive.ubuntu.com natty/restricted Translation-es
Hit http://archive.ubuntu.com natty/universe Translation-es
Hit http://archive.ubuntu.com natty-updates/main Sources
Hit http://archive.ubuntu.com natty-updates/restricted Sources
Hit http://archive.ubuntu.com natty-updates/universe Sources
Hit http://archive.ubuntu.com natty-updates/multiverse Sources
Hit http://archive.ubuntu.com natty-updates/main i386 Packages
Hit http://archive.ubuntu.com natty-updates/restricted i386 Packages
Hit http://archive.ubuntu.com natty-updates/universe i386 Packages
Hit http://archive.ubuntu.com natty-updates/multiverse i386 Packages
Hit http://archive.ubuntu.com natty-security/main Sources
Hit http://archive.ubuntu.com natty-security/restricted Sources
Hit http://archive.ubuntu.com natty-security/universe Sources
Hit http://archive.ubuntu.com natty-security/multiverse Sources
Hit http://archive.ubuntu.com natty-security/main i386 Packages
Hit http://archive.ubuntu.com natty-security/restricted i386 Packages
Hit http://archive.ubuntu.com natty-security/universe i386 Packages
Hit http://archive.ubuntu.com natty-security/multiverse i386 Packages
Ign http://archive.ubuntu.com natty/main Translation-en_US
Ign http://archive.ubuntu.com natty/main Translation-en
Ign http://archive.ubuntu.com natty/multiverse Translation-en_US
Ign http://archive.ubuntu.com natty/multiverse Translation-en
Ign http://archive.ubuntu.com natty/restricted Translation-en_US
Ign http://archive.ubuntu.com natty/restricted Translation-en
Ign http://archive.ubuntu.com natty/universe Translation-en_US
Ign http://archive.ubuntu.com natty/universe Translation-en
Ign http://archive.ubuntu.com natty-updates/main Translation-en_US
Ign http://archive.ubuntu.com natty-updates/main Translation-en
Ign http://archive.ubuntu.com natty-updates/main Translation-es
Ign http://archive.ubuntu.com natty-updates/multiverse Translation-en_US
Ign http://archive.ubuntu.com natty-updates/multiverse Translation-en
Ign http://archive.ubuntu.com natty-updates/multiverse Translation-es
Ign http://archive.ubuntu.com natty-updates/restricted Translation-en_US
Ign http://archive.ubuntu.com natty-updates/restricted Translation-en
Ign http://archive.ubuntu.com natty-updates/restricted Translation-es
Ign http://archive.ubuntu.com natty-updates/universe Translation-en_US
Ign http://archive.ubuntu.com natty-updates/universe Translation-en
Ign http://archive.ubuntu.com natty-updates/universe Translation-es
Ign http://archive.ubuntu.com natty-security/main Translation-en_US
Ign http://archive.ubuntu.com natty-security/main Translation-en
Ign http://archive.ubuntu.com natty-security/main Translation-es
Ign http://archive.ubuntu.com natty-security/multiverse Translation-en_US
Ign http://archive.ubuntu.com natty-security/multiverse Translation-en
Ign http://archive.ubuntu.com natty-security/multiverse Translation-es
Ign http://archive.ubuntu.com natty-security/restricted Translation-en_US
Ign http://archive.ubuntu.com natty-security/restricted Translation-en
Ign http://archive.ubuntu.com natty-security/restricted Translation-es
Ign http://archive.ubuntu.com natty-security/universe Translation-en_US
Ign http://archive.ubuntu.com natty-security/universe Translation-en
Ign http://archive.ubuntu.com natty-security/universe Translation-es
Fetched 31,4 kB in 1min 21s (384 B/s)
W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/natty/Release.gpg  Bad header line [IP: 91.189.92.171 80]

W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/natty-security/Release.gpg  Bad header line [IP: 91.189.92.171 80]

W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/natty/main/i18n/Translation-en_US  Bad header line

W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/natty/main/i18n/Translation-en  Bad header line

E: Some index files failed to download. They have been ignored, or old ones used instead.
I followed this solution found in google:

Code:
$ cd /var/lib/apt
$ sudo mv lists lists.old
$ sudo mkdir -p lists/partial
$ sudo apt-get update
but nothing, so i reinsatalled from another iso to see if that was the problem.. its the same. I dont know what to do. 

I also set default keys with the button found in authentification in sources dialog... and changed sources from main to my local mirros. Its the same...

i hope the next release is better, because natty has been a huge hindrance from the very beginning 

any help please? Its frustrating...