How do I fix APT errors "W: Failed to fetch [...] Hash Sum mismatch"?

I don't really know what happened, after reboot I got many crash messages, and if I would open Firefox or Synaptic, they would crash. Synaptic returns this:

E: Encountered a section with no Package: header
E: Problem with MergeList /var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_raring-security_main_i18n_Translation-en
E: The package lists or status file could not be parsed or opened.
E: _cache->open() failed, please report.

Then crash icon on the top panel appeared, and there was some error about mergelist. I googled, and found this sudo rm /var/lib/apt/lists/* -vf sudo apt-get update That didn't work. To be able to work in browser I deleted all files in /var/lib/apt/lists. If I try sudo apt-get update, I get this:

W: Failed to fetch gzip:/var/lib/apt/lists/partial/ua.archive.ubuntu.com_ubuntu_dists_raring_main_source_Sources Hash Sum mismatch
W: Failed to fetch gzip:/var/lib/apt/lists/partial/ua.archive.ubuntu.com_ubuntu_dists_raring_restricted_source_Sources Hash Sum mismatch
W: Failed to fetch gzip:/var/lib/apt/lists/partial/ua.archive.ubuntu.com_ubuntu_dists_raring_universe_source_Sources Hash Sum mismatch
W: Failed to fetch gzip:/var/lib/apt/lists/partial/security.ubuntu.com_ubuntu_dists_raring-security_main_source_Sources Hash Sum mismatch
W: Failed to fetch gzip:/var/lib/apt/lists/partial/security.ubuntu.com_ubuntu_dists_raring-security_universe_source_Sources Hash Sum mismatch
W: Failed to fetch gzip:/var/lib/apt/lists/partial/security.ubuntu.com_ubuntu_dists_raring-security_main_binary-i386_Packages Hash Sum mismatch
W: Failed to fetch gzip:/var/lib/apt/lists/partial/security.ubuntu.com_ubuntu_dists_raring-security_universe_binary-i386_Packages Hash Sum mismatch
E: Some index files failed to download. They have been ignored, or old ones used instead.

I do not want to reinstall the system. How could I fix that? Thanks.

Some photos there. I can't make screenshots, it crashes: Photo 1 Photo 2

The problem is that you deleted recursively /var/lib/apt/lists, which deleted the partial directory too. So, recreating the directory should solve the issue:

sudo mkdir -p /var/lib/apt/lists/partial
sudo chmod 755 /var/lib/apt/lists/partial

Also, is possible that the mirror you are using have problems. Select another mirror and update again.

For me something is wrong in Ukrainian server! Changing to main automatically solves the problem. Please try different server if nothing of above was helpful.