Hi- I couldn't install MonetDB on Ubuntu 16.04.1 LTS (Xenial Xerus) hosted on EC2 yesterday. I kept getting the error below. It looks like the repository does not have a "source" folder. However, I noticed that the "Trusty" version had a "source" folder, and so I tried installing the Trusty version on my Xenial box, and it installed successfully. So far, I haven't encountered any problems, but was there anything I did wrong in the installation process? Will I encounter problems down the road with the Trusty version installed on a Xenial box? $ sudo apt-get update Hit:1 http://us-east-1.ec2.archive.ubuntu.com/ubuntu xenial InRelease Hit:2 http://us-east-1.ec2.archive.ubuntu.com/ubuntu xenial-updates InRelease Hit:3 http://us-east-1.ec2.archive.ubuntu.com/ubuntu xenial-backports InRelease Get:4 http://security.ubuntu.com/ubuntu xenial-security InRelease [94.5 kB] Ign:5 http://dev.monetdb.org/downloads/deb xenial InRelease Get:6 http://dev.monetdb.org/downloads/deb xenial Release [2,715 B] Get:7 http://dev.monetdb.org/downloads/deb xenial Release.gpg [163 B] Fetched 97.3 kB in 0s (185 kB/s) Reading package lists... Done W: http://dev.monetdb.org/downloads/deb/dists/xenial/Release.gpg: Signature by key 213E64DCD5DDC2C063CC39FD053C3ED40583366F uses weak digest algorithm (SHA1) E: Failed to fetch http://dev.monetdb.org/downloads/deb/dists/xenial/Release Unable to find expected entry 'monetdb/source/Sources' 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.