<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta content="text/html; charset=UTF-8" http-equiv="Content-Type"> </head> <body text="#000000" bgcolor="#ffffff"> What does your /etc/apt/sources.list file contain? Do you add entries to older distros that may not be supported anymore? On 28/05/2011 13:42, Robin Bownes wrote: <blockquote cite="mid:1306582951.1832.5.camel@robin-Aspire-5332" type="cite"> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <meta name="GENERATOR" content="GtkHTML/3.32.2"> When I try to update repository information, I get the following error message: W:Failed to fetch gzip:/var/lib/apt/lists/partial/za.archive.ubuntu.com_ubuntu_dists_natty_main_source_Sources Hash Sum mismatch , E:Some index files failed to download. They have been ignored, or old ones used instead. I do get some application updates, but Update Manager constantly tells me to upgrade repository information because it has not been updated for x number of days. I have been experiencing this problem since upgrading to Natty. However, my wife, who is still running 10.10 is experiencing a similar problem, although her error message of course lists a different repository as being problematic. </blockquote> </body> </html>