For two days now Evolution reports the following error when I try to connect to my university’s mail-server:
imap.server.name:993« gescheitert: Cannot communicate securely with peer: no common encryption algorithm(s).
Before this issue I had no problems with receiving/sending mails via this server.
I use ubuntu 14.04 LTS and gnome-shell.
Since I am a real linux-beginner I would prefer step-by-step instructions.
This is a known bug. A fix is in the works. If it is urgent, you can enable the -proposed branch of the repositories (see How do I add the "proposed" repository?) and install the test version of Evolution uploaded (which contains the fix). Or you could wait a few days for the tested version to be released in other channels.
I am having the same problem. There is a serious vulnerability in SSL that is causing people who run servers to disable support for a very old version of the protocol, and inexplicably it seems that Evolution only supports this very old protocol instead of much newer, safer ones. It seems that a fix exists, and Ubuntu needs to get on their horse and release a new package. I opened this bug about the issue, so you could follow that for potential updates.
Beyond that, though, the best course of action is probably to sit tight until an update happens. You could try using a third-party PPA to install a newer version which may or may not have the fix, but as a beginner you might find that process difficult, and since the evolution packages are all tied to the rest of the Gnome3 behemoth, updating evolution generally means updating all of Gnome3, and having tried that before, I would describe it as immensely painful and unrewarding.
On the bright side, your university's IT team deserves some kudos for responding that promptly to the vulnerability.
Your university disabled SSLv3 because of vulnerabilities in the encryption called the "Poodle" attack.
The thing is: An attacker might force you to use SSLv3 by aquiring a man-in-the-middle position (which is fairly easy e.g. on a wireless network). Then, when you try to read your emails, he will downgrade your encrypted connection to the mail server to SSLv3. This communication protocol is not easily breakable, but it does have some weaknesses, one of which was discovered recently: An attacker can keep guessing some bits at the end of a network package. And it will only take him a few (~1000) guesses until he gets the whole session cookie (the one authenticating your facebook (email, ebay, amazon ...) session so you won't have to enter your password every time you reload the page or follow an internal link) right.
At that time, he will be able to hijack your facebook (email, ebay, amazon ...) account. To prevent this from happening, server administrators are removing the option to use SSLv3 entirely. Almost every device supports better encryption protocols, so it is not really necessary anymore.
If you want to check if your browser is vulnerable to the attack, there is a test page here: Poodle Test
Apparently, evolution did update their encryption to not depend on SSLv3 anymore only recently. But the evolution version in the official repositorys is pretty outdated, which means that you COULD build evolution from source, but I personally do not recommend doing it. Another way is to enable the proposed repositories and install it from there, or just wait until the new version is moved to the official repo and evolution is updated via system update.
