Hello, this issue is probably a duplicate of [776746]. See especially message #91. For a "simple" explanation see [1251281], message 31.
[776746] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=776746 [1251281] https://bugs.launchpad.net/ubuntu/+source/gnome-session/+bug/1251281/comments/31 Some details on my test setup: I have tried to reproduce it by a i386 qemu-VM: qemu-system-i386 --enable-kvm -cpu host -m 1G -drive file=debian-8-jessie-i386-gnome-install.qemu.img,cache=writeback -redir tcp:2222::22 -redir tcp:3389::3389 -net nic -net user Then connected from localhost to the VM: xfreerdp localhost Select "sesman-Xvnc" and enter user crendentials. Then a small window with some logging output is shown. Then this message is shown: Oh no! Something has gone wrong. A problem has occured and the system can't recover. Please log out and try again. Log Out (button) benutzer@debian:~$ tail -f .xsession-errors Xsession: X session started for at Mi 20. Mai 13:50:18 CEST 2015 X Error of failed request: BadValue (integer parameter out of range for operation) Major opcode of failed request: 109 (X_ChangeHosts) Value in failed request: 0x5 Serial number of failed request: 6 Current serial number in output stream: 8 localuser:benutzer being added to access control list openConnection: connect: Datei oder Verzeichnis nicht gefunden cannot connect to brltty at :0 gnome-session-is-accelerated: No composite extension. gnome-session-check-accelerated: Helper exited with code 256 gnome-session-is-accelerated: No composite extension. gnome-session-check-accelerated: Helper exited with code 256 ** (process:996): WARNING **: software acceleration check failed: Child process exited with code 1 As a workaround tried to build a tigervnc package: mkdir tigervnc; cd tigervnc dget https://dl.bintray.com/tigervnc/stable/ubuntu-14.04LTS/source/tigervnc_1.4.3-3ubuntu1.dsc dpkg-source -x tigervnc_1.4.3-3ubuntu1.dsc cd tigervnc-1.4.3/ dch --local local "build for jessie" sed -i 's/libjpeg-turbo8/libjpeg62-turbo/' debian/control sed -i 's/libgcrypt11/libgcrypt20/' debian/control sed -i 's/libgnutls28,/libgnutls-deb0-28,/' debian/control sed -i 's/libt1-dev, /libcairo2-dev, libgcrypt20-dev, x11proto-xcmisc-dev, /' debian/control dpkg-buildpackage cd .. su dpkg --purge vnc4server dpkg -i tigervncserver_1.4.3-3ubuntu1local1_i386.deb reboot This package shows not anymore this error. But unfortunately this is just usefull if one has a very high resolution as "someone" tries always to resize to 1920x1200. Starting xfreerdp that way it seems to work normal (as far as I can see with my screen resolution): xfreerdp /w:1920 /h:1200 /v:localhost Kind regards, Bernhard -- To UNSUBSCRIBE, email to debian-bugs-rc-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org