I am unable to set the timezone display correctly.
I try o set Mountain Standard time (GMT -7) and the correct time; I get

Unable to authenticate/execute the action:6,

then a crash and

Application: KDE Control Module (kcmshell4), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f5f13a507c0 (LWP 7731))]

Thread 3 (Thread 0x7f5ef7da1700 (LWP 7732)):
#0 0x00007f5f133763cd in poll () from /lib/x86_64-linux-gnu/libc.so.6
#1 0x00007f5f0df951dc in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2 0x00007f5f0df956ba in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3 0x00007f5ef80914f6 in ?? () from /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#4 0x00007f5f0dfb8eb5 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5 0x00007f5f0eab1f8e in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0
#6 0x00007f5f13382e1d in clone () from /lib/x86_64-linux-gnu/libc.so.6

Thread 2 (Thread 0x7f5ef68e4700 (LWP 7733)):
#0 0x00007f5f13374b0d in read () from /lib/x86_64-linux-gnu/libc.so.6
#1 0x00007f5f0dfd36cf in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2 0x00007f5f0df94d3c in g_main_context_check () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3 0x00007f5f0df95175 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4 0x00007f5f0df95304 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5 0x00007f5f11f9c036 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#6 0x00007f5f11f6c38f in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#7 0x00007f5f11f6c618 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#8 0x00007f5f11e6e410 in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#9 0x00007f5f11f4dedf in ?? () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#10 0x00007f5f11e70bec in ?? () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#11 0x00007f5f0eab1f8e in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0
#12 0x00007f5f13382e1d in clone () from /lib/x86_64-linux-gnu/libc.so.6

Thread 1 (Thread 0x7f5f13a507c0 (LWP 7731)):
[KCrash Handler]
#5 0x0000000000000001 in ?? ()
#6 0x00007f5f11f856a3 in QObject::connect(QObject const*, char const*, QObject const*, char const*, Qt::ConnectionType) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#7 0x00007f5f11f8ae1a in ?? () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#8 0x00007f5f11f8af66 in QTimer::singleShot(int, QObject*, char const*) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#9 0x00007f5f027224b6 in ?? () from /usr/lib/kde4/kcm_clock.so
#10 0x00007f5f1306b807 in KCModuleProxy::save() () from /usr/lib/libkcmutils.so.4
#11 0x00007f5f13067b60 in ?? () from /usr/lib/libkcmutils.so.4
#12 0x00007f5f11f820ef in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#13 0x00007f5f12cf410f in KPushButton::authorized(KAuth::Action*) () from /usr/lib/libkdeui.so.5
#14 0x00007f5f11f820ef in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#15 0x00007f5f1197ec82 in QAbstractButton::clicked(bool) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#16 0x00007f5f116d223e in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#17 0x00007f5f116d2a30 in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#18 0x00007f5f116d2c9c in QAbstractButton::mouseReleaseEvent(QMouseEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#19 0x00007f5f11360a89 in QWidget::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#20 0x00007f5f113138ec in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#21 0x00007f5f11316a33 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#22 0x00007f5f12c311a6 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#23 0x00007f5f11f6d63e in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#24 0x00007f5f11319933 in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#25 0x00007f5f1138eec4 in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#26 0x00007f5f1138def1 in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#27 0x00007f5f113b90b2 in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#28 0x00007f5f0df94f05 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#29 0x00007f5f0df95248 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#30 0x00007f5f0df95304 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#31 0x00007f5f11f9c016 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#32 0x00007f5f113b91ae in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#33 0x00007f5f11f6c38f in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#34 0x00007f5f11f6c618 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#35 0x00007f5f117ce1c8 in QDialog::exec() () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#36 0x00007f5f13658b1c in kdemain () from /usr/lib/kde4/libkdeinit/libkdeinit4_kcmshell4.so
#37 0x00007f5f132aaea5 in __libc_start_main () from /lib/x86_64-linux-gnu/libc.so.6
#38 0x0000000000400701 in _start ()

This has been with me for a long time. I ignored it in hopes it would just go away but

help!

Thank you for your time

Moved to Workspace.

Which distro do you use? What KDE Plasma Desktop version?

env | grep GLIB

polkit-kde-authentication-agent-1 does not work properly unless it uses the glib event queue (because it interacts with some gobjects and they don't work at all without it...)

If the above command prints anything like "QT_NO_GLIB=1", run
pkill polkit-kde-auth
QT_NO_GLIB=0 /usr/lib/kde4/libexec/polkit-kde-authentication-agent-1

fix the problem this way :

1. In Digital Clock settings ----> Time Zone choose your city,

2. In Adjust Date and Time -----> Time Zones choose UTC

Click on apply and OK and the server changes to the right time.

Right click on the clock at the right. Select "Digital Clock Settings".

In the settings window, select "Time Zones".

At the bottom of the Time Zones window, there's a "Clock Defaults to" choice. For me that gives a choice of "local" or "UTC", and is currently set to "local". Above that, there's a long list of timezones. Currently, I see UTC checked there. The effect is that UTC, in addition to local time, shows when the mouse is over the clock. If I uncheck "UTC", then only the local time shows.

I hope that helps.