I have Xfce, I have up-to-date F16 with xfce4-power-manager-1.0.10-1.fc16.x86_64. The setting dialog for PWM says that PWM does not run (unable to connect to PWM) even PWM is running. I killed PWM and then: strace -f -s1024 xfce4-power-manager --sync ended with: [pid 22308] write(2, "\nGdk-ERROR **: The program 'xfce4-power-manager' received an X Window System error.\nThis probably reflects a bug in the program.\nThe error was 'BadName (named color or font does not exist)'.\n (Details: serial 494 error_code 15 request_code 149 minor_code 11)\n (Note to programmers: normally, X errors are reported asynchronously;\n that is, you will receive the error a while after causing it.\n To debug your program, run it with the --sync command line\n option to change this behavior. You can then get a meaningful\n backtrace from your debugger if you break on the gdk_x_error() function.)\n", 601) = 601 This bug is present since early F16 Alpha. It worked in F15.
After installing latest updates, error messages changed: [mrunge@sofja ~]$ xfce4-power-manager --no-daemon (xfce4-power-manager:2650): libnotify-WARNING **: Failed to connect to proxy (xfce4-power-manager:2650): xfce4-power-manager-WARNING **: could not map keysym 1008ffa8 to keycode Gdk-ERROR **: The program 'xfce4-power-manager' received an X Window System error. This probably reflects a bug in the program. The error was 'BadName (named color or font does not exist)'. (Details: serial 301 error_code 15 request_code 149 minor_code 11) (Note to programmers: normally, X errors are reported asynchronously; that is, you will receive the error a while after causing it. To debug your program, run it with the --sync command line option to change this behavior. You can then get a meaningful backtrace from your debugger if you break on the gdk_x_error() function.) Trace/breakpoint trap
Maybe related, sadly no solution: https://bugzilla.xfce.org/show_bug.cgi?id=7999
Confirmed on i686. Kernel: 3.1.0-7.fc16.i686 Package: xfce4-power-manager-1.0.10-1.fc16.i686 $ xfce4-power-manager --no-daemon (xfce4-power-manager:20517): libnotify-WARNING **: Failed to connect to proxy (xfce4-power-manager:20517): xfce4-power-manager-WARNING **: could not map keysym 1008ffa8 to keycode Gdk-ERROR **: The program 'xfce4-power-manager' received an X Window System error. This probably reflects a bug in the program. The error was 'BadName (named color or font does not exist)'. (Details: serial 297 error_code 15 request_code 149 minor_code 11) (Note to programmers: normally, X errors are reported asynchronously; that is, you will receive the error a while after causing it. To debug your program, run it with the --sync command line option to change this behavior. You can then get a meaningful backtrace from your debugger if you break on the gdk_x_error() function.) Trace/breakpoint trap
Confirmed on x86_64, but the error is slightly different. Kernel: 3.1.0-7.fc16.x86_64 Package: xfce4-power-manager-1.0.10-1.fc16.x86_64 # xfce4-power-manager --no-daemon (xfce4-power-manager:3082): xfce4-power-manager-WARNING **: Unable to connect to session managet : Failed to connect to the session manager: SESSION_MANAGER environment variable not defined (xfce4-power-manager:3082): xfce4-power-manager-WARNING **: could not map keysym 1008ffa8 to keycode Gdk-ERROR **: The program 'xfce4-power-manager' received an X Window System error. This probably reflects a bug in the program. The error was 'BadName (named color or font does not exist)'. (Details: serial 297 error_code 15 request_code 149 minor_code 11) (Note to programmers: normally, X errors are reported asynchronously; that is, you will receive the error a while after causing it. To debug your program, run it with the --sync command line option to change this behavior. You can then get a meaningful backtrace from your debugger if you break on the gdk_x_error() function.) Trace/breakpoint trap
dmesg output: xfce4-power-man[3082] trap int3 ip:7fef1552a2c3 sp:7fff6ca02df0 error:0
I believe this is linked to the fact that the brightness control applet is crashing on startup. This is very sad...
xfce4-power-manager-1.0.10-2.fc16 has been submitted as an update for Fedora 16. https://admin.fedoraproject.org/updates/xfce4-power-manager-1.0.10-2.fc16
xfce4-power-manager-1.0.10-2.fc16 has been pushed to the Fedora 16 stable repository. If problems still persist, please make note of it in this bug report.