I have the same problem with my company's email which uses the Rackspace Outlook 2016 Exchange service. Rackspace told me that they cannot change the DH key to a value higher than 1024 bits (which I don't believe) and they suggested that instead the company upgrades to some Office 365 service which supports a higher DH key size. So, at this moment I cannot use my company's Exchange E-mail from Evolution as I could in the past.
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-online-accounts in Ubuntu. https://bugs.launchpad.net/bugs/1860461 Title: libgnutls30 3.6.11.1-2ubuntu2 (Ubuntu 20.04) breaks pulseui client with error "Error performing TLS handshake: The Diffie-Hellman prime sent by the server is not acceptable (not long enough)." Status in evolution package in Ubuntu: Confirmed Status in gnome-online-accounts package in Ubuntu: Confirmed Status in gnutls28 package in Ubuntu: Confirmed Bug description: After upgrade to 20.04 package libgnutls30 broke pulseUI VPN client with the following error: "Error performing TLS handshake: The Diffie-Hellman prime sent by the server is not acceptable (not long enough)." I had to revert the package to the 19.10 version (3.6.9-5ubuntu1) and to install 19.10 dependency libhogweed4 3.4.1-1 to fix it. ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: libgnutls30 3.6.9-5ubuntu1 ProcVersionSignature: Ubuntu 5.4.0-9.12-generic 5.4.3 Uname: Linux 5.4.0-9-generic x86_64 ApportVersion: 2.20.11-0ubuntu15 Architecture: amd64 Date: Tue Jan 21 17:48:39 2020 InstallationDate: Installed on 2017-06-21 (943 days ago) InstallationMedia: Ubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412) SourcePackage: gnutls28 UpgradeStatus: Upgraded to focal on 2020-01-10 (10 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/evolution/+bug/1860461/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
