Update: cannot load repository info topic

L-Ub 12.04 (I think). Ran update manager. Initial list was:

Changes for the versions:
Installed version: 5.09-2ubuntu0.5
Available version: 5.09-2ubuntu0.6

Version 5.09-2ubuntu0.6:

* SECURITY UPDATE: DoS via insufficient note headers
- debian/patches/CVE-2014-3710.patch: handle running out of not headers
in src/readelf.c.
- CVE-2014-3710
* SECURITY UPDATE: DoS in ELF parser
- debian/patches/CVE-2014-8116.patch: limit number of headers and
capabilities in src/elfclass.h, src/readelf.c.
- CVE-2014-8116
* SECURITY UPDATE: DoS via missing recursion limits
- debian/patches/CVE-2014-8117.patch: lower recursion level and allow
it to be set from the command line in src/file.{c,h},
src/file_opts.h, src/funcs.c, src/magic.c, src/magic.h,
src/softmagic.c, add new option to documentation in
doc/file.man, doc/libmagic.man.
- CVE-2014-8117
* SECURITY UPDATE: DoS via long pascal strings
- debian/patches/pr398-truncate-pascal-strings.patch: correctly
calculate size in src/softmagic.c.
- No CVE number




Check button produced these errors:

Failed to download repository info:

W:Failed to fetch http://ppa.launchpad.net/michael-gru...source/Sources 404 Not Found
, W:Failed to fetch http://ppa.launchpad.net/michael-gru...-i386/Packages 404 Not Found
, E:Some index files failed to download. They have been ignored, or old ones used instead.



Please any advice? Thank you