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When I do a
sudo apt-get update, I encounter the following:
Fetched 189 B in 10s (18 B/s) W: There is no public key available for the following key IDs: 1397BC53640DB551 W: GPG error: http://download.opensuse.org ./ Release: The following signatures were invalid: KEYEXPIRED 1436387333 W: Failed to fetch http://dl.google.com/linux/chrome/deb/dists/stable/Release Unable to find expected entry 'main/binary-i386/Packages' in Release file (Wrong sources.list entry or malformed file) E: Some index files failed to download. They have been ignored, or old ones used instead.
What would be a good/recommended way to fix this?