Update Manager failing 10.10

[craynium]

just recently started having problems with Update Manager. Getting this error on many packages while attempting upgrade.
I receive the same errors when using main or US server setting.

Running 10.10 with 2.6.35-27-generic


Failed to fetch http://us.archive.ubuntu.com/ubuntu/pool/main/a/avahi/avahi-utils_0.6.27-2ubuntu3.1_i386.deb Size mismatch
Failed to fetch http://us.archive.ubuntu.com/ubuntu/pool/main/p/pm-utils/pm-utils_1.4.1-3ubuntu1_all.deb Size mismatch
Failed to fetch http://us.archive.ubuntu.com/ubuntu/pool/main/p/poppler/poppler-utils_0.14.3-0ubuntu1.2_i386.deb Size mismatch

[cjejuni]

i think i had a few hours ago! if your system usable at least to see internet, hold your upgrading mouse. there is something array with the dpkg, apt-get, aptitude, synaptic pkg manager lists, config files! somehow they are using the same files. look/see with aptitude where it is broken, kinda look like windows3.1 (no pun intended.)
post the error so other can help too.
good luck.

[cjejuni]

try this thread:

http://ubuntuforums.org/showthread.php?t=1705101

cj