sudo apt-get update failes due to Hash Sum mismatch [duplicate]
Solution 1:
Run these commands in terminal 1:
sudo apt-get clean
sudo rm -r /var/lib/apt/lists/*
That worked for me. :-)
Reference
Solution 2:
Usually switching to another mirror does the trick. It's easy in the GUI, but I suspect you want a CLI solution.
sudo sed -i 's|http://us.|http://|g' /etc/apt/sources.list
edits your sources.list in-place to use the main server from the US mirror. You can substitute other mirrors, sudo sed -i 's|http://us.|http://fr.|g' /etc/apt/sources.list
would choose the french server, starting from the US server.
If you switch to the main server like in the first line, be warned that simple swapping your search and replace terms to get the US mirror back would break your security and extras repos, if you use them. You would need to run a second sudo sed -i 's|http://us.security|http://security|g' /etc/apt/sources.list
line to account for that, repeated for extras instead of security.