*** This bug is a duplicate of bug 1872778 *** https://bugs.launchpad.net/bugs/1872778
As a workaround, can you try lowering the profile from MEDIUM [1] to LOW [2]: sudo mkdir /etc/gnutls cat << EOF | sudo tee -a /etc/gnutls/config [overrides] default-priority-string = NORMAL:-VERS-ALL:+VERS-TLS1.3:+VERS-TLS1.2:+VERS-DTLS1.2:%PROFILE_LOW EOF 1: https://git.launchpad.net/ubuntu/+source/gnutls28/tree/debian/rules#n38 2: https://gnutls.org/manual/html_node/Selecting-cryptographic-key-sizes.html#Selecting-cryptographic-key-sizes -- 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/1866974 Title: The Diffie-Hellman prime sent by the server is not acceptable Status in evolution package in Ubuntu: Confirmed Status in gnome-online-accounts package in Ubuntu: New Bug description: I can no longer connect to my ISP mail server. Works in previous version 19.10 "The reported error was “Failed to get capabilities: Error performing TLS handshake: The Diffie-Hellman prime sent by the server is not acceptable (not long enough).”." I've tried finding a workaround but so far no luck. ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: evolution 3.35.92-1 ProcVersionSignature: Ubuntu 5.4.0-18.22-generic 5.4.24 Uname: Linux 5.4.0-18-generic x86_64 NonfreeKernelModules: nvidia_modeset nvidia ApportVersion: 2.20.11-0ubuntu20 Architecture: amd64 CurrentDesktop: ubuntu:GNOME Date: Wed Mar 11 11:07:01 2020 InstallationDate: Installed on 2020-03-03 (7 days ago) InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Alpha amd64 (20200303) SourcePackage: evolution UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/evolution/+bug/1866974/+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