I'm coming from windows and still new to Ubuntu.  Occasionally everything freezes and I lose my taskbar and launcher.  What do I do?  What's the Ubuntu equivalent of ctrl+alt+del in Windows? I tried alt+f2 to bring up the "special terminal," but what can I do from there?  I tried "sudo shutdown now" but that didn't fully shut down the computer and I needed a hard shutdown.  If I do manage to figure out what's wrong and fix it from the alt+f2 terminal, how do I get back to the desktop?
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All operating systems freeze sometimes, and Ubuntu is no exception. What should I do to regain control when...   just one program stops responding? nothing at all responds to mouse clicks or key presses? the mouse stops moving entirely? I have an    In what order should I try various solutions before deciding to pull the power plug?  What should I do when starting up Ubuntu fails?  Is there a diagnostic procedure I can follow?
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Since one or two months ago, my laptop with ubuntu 12.10x64 hangs during shutdown. There's just a black screen, no harddisk activity, it justs sits there. I feel it happens near the end of a normal shutdown cycle, judging from time elapsed.  Only resolution is hard power-off (holding power key for several seconds) - neither Ctrl-Alt-Backspace (which normally works, I have it switched on in Settings) nor Ctrl-Alt-Del help, nor can I get into a text console with Ctrl-Alt-F1.   How do I diagnose that? It does not happen on every shutdown, but often enough to be annoying (as it forces a diskcheck on reboot, of course).   Which log files can tell me what's going wrong? More or less blindly searching in the sys log viewer reminds me of needles in a haystack.  I imagine I could pinpoint the time it happens via log timestamps, but how do I read timestamps like e.g. in kern.log: [36169.146130]? How do I get this human-readable?  Lastly, a bit of a btw, I've never managed to execute an Alt-Sysrq-REISUB to force a cleaner shutdown, but that's probably because I'm on a laptop, PrintScr is only accessible via an Fn key, and I'm not sure of the exact key sequence I need. Is there a "harmless" but user-visible magic command I could practice this with (during normal operation), so I can find out how to do a REISUB next time?  Thanks all! Comment if you need additional data...
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I'm brand new to Linux. I just installed Ubuntu as a dual boot system on my HP Pavilion laptop.  Where should I start? I've tried to play around with Terminal over the last hour or so, but I'm probably not helping myself out. Any suggestions are welcome!
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Can anyone explain how to swap Caps Lock and Ctrl keys on Ubuntu desktop under Unity. I use it to avoid .
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I'm getting no Dash / Launcher after I login. This started after an update through the Software updater. Please help to fix ... I've already lost a day trying different options posted on askubuntu.com. Nothing worked.  Got to the terminal via Ctl + Alt + F1 and logged-in successfully.  Here are the logs: .xsession-errors Script for ibus started at run_im. init: unity-panel-service main process (2315) terminated with status 1 init: indicator-printers main process (2459) terminated with status 1 init: unity-settings-daemon main process (2300) terminated with status 1 init: upstart-dbus-session-bridge main process (2293) terminated with status 1 init: hud main process (2304) killed by TERM signal init: indicator-bluetooth main process (2446) killed by TERM signal init: indicator-power main process (2448) killed by TERM signal init: indicator-datetime main process (2451) killed by TERM signal init: indicator-sound main process (2453) killed by TERM signal init: indicator-session main process (2483) killed by TERM signal init: indicator-application main process (2486) killed by TERM signal init: Disconnected from notified D-Bus bus   UPDATE (Jun 8, 2014):  Okay, I have reset unity, but I cannot login normally via the login screen. Steps I follow: 1. Login screen -&gt; blank ... No dash / no launcher / No Status (Notification) Bar on top 2. Ctrl+Alt+F1 to bash terminal 3. export DISPLAY=:0 4. unity-tweak-tool --reset-unity (This does not complete, blocks on OpenGL) 5. I anyways continue to by doing: Ctrl+Alt+F7. 6. Launcher &amp; Dash look good. But there is (a) No Status / Notification Bar on top 7. Continuing to work this way. Haven't logged out since.
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I have an Ubuntu 10.04 LTS Desktop PC with GNOME.   How can I fully disable the reboot/shutdown/suspend/hibernate functions in GNOME or even with root? So that the root gives out the "reboot" or "pm-suspend" command it doesn't do anything, and the machine goes on. How can I fully disable these basic "features"?
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I used to close a running application by pressing ALT+F4. But, I realised that the application is still running and the correct way to close (quit) it is the combination of Ctrl+Q keys.  So, what is the purpose of ALT+F4 and how is it different from Ctrl+Q?
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I've recently installed Ubuntu 18.04 in a dual-boot configuration with Windows 10. I noticed today that, when trying to open system settings, Ubuntu seems to log me out to the lock screen. When I log back in, all previously-running applications are now closed. Very unsure what to do from here, any help much appreciated.
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It's a situation that has happened quite often to me: after I press (with a different intention) Ctrl-S in a terminal, the interaction (input or output) with it is frozen. It's probably a kind of "scroll lock" or whatever.  How do I unfreeze the terminal after this?  (This time, I have been working with apt-shell inside a bash inside urxvt--not sure which of them is responsible for the special handling of Ctrl-S: I was searching the history of commands backwards with C-r, as usual for readline, but then I wanted to go "back" forwards through the history with the usual--at least in Emacs--C-s (, , ), but that caused the terminal to freeze. Well, scrolling/paging to view past things still works in the terminal, but no interaction with the processes run there.)
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I just ran this a few seconds ago. I managed to do Ctrl - C as soon as I realized what I started doing.  So far the only directory it's started going through is /bin.  I'm afraid to do anything else. So far I realized I can't use su as my normal user anymore.  Luckily I still have another root terminal open. What do I do?
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I'm moving across from Mac OSX and am quite used to using the Cmd-Q shortcut to quit apps. I appreciate that Linux is set up differently and that different apps have different shortcuts for quitting (e.g. some use Ctrl-Q while others might be Alt-Q, etc.). I'm currently using Ubuntu GNOME.  Would it be possible to create a standard keyboard shortcut for quitting all apps easily and safely in Ubuntu? I'm happy to use a third-party tool or do a bit of further digging.  M
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Is there any UI in ubuntu like the one in Windows to kill the processes forcefully.  My google chrome application is stuck and i can't close it, need to do it forcefully.Please help !
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Is there a way that I can stop the Ctrl+Alt+F4 key combination from switching to a virtual terminal?  I still want the other key combinations to switch to terminals - I just want to change the F4 one because I often use that keyboard shortcut in a Windows VM.
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Between Ctrl and Alt, modern keyboards have an abominable key: the 'Windows' key :P    By default, when this key is pressed alone it opens the Start menu. Many applications and a great number of games work in fullscreen mode, and if you press this key accidentally, most of times because you wanted to press the Ctrl or Alt keys, the application usually freezes for a while and  minimizes itself. If you are lucky, your videogame will pause, but sometimes it continues even when it is minimized.  Is it possible to disable the 'Windows' key?  It would be possible to show the Start menu with another combination of keys? I would like to keep combinations that use the Windows key working, like Windows+L, which leaves current session.
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From the usual Ubuntu login screen, I click on my name, type my password, and press ENTER.  Screen goes black...and stays black.  I cannot get to my desktop.  If I SSH from another computer and run htop, I can see /usr/bin/gnome-shell is eating up 100% of a single core.  Other than gnome-shell, the system is completely idle.  Load average in htop is exactly 1.00.    Earlier today I left it there for over an hour, but no change.  Since then I've also tried rebooting, but same results.  This desktop was previously working fine, not sure what I messed up.  How can I debug what is happening?
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I faced with a problem after update,   I missed 2 buttons from above panel, System menu (including shutdown, suspend &amp; …) and User (including log out &amp; …)  how can I restore them !?...
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What happened  I was working on my laptop while it upgraded from 15.10 to 16.04 (which I admit was a mistake) when suddenly the Unity overlay disappeared and the only thing on screen was the Firefox browser window. I switched to a new terminal, logged in and tried to run sudo service lightdm restart but instead of restarting correctly, the screen started turning on and off repeatedly, which freaked me out, so I physically turned off the PC.  Long story short: I forced a shutdown halfway through the Ubuntu upgrade.  Ever since, any attempts of logging in normally have been met with a solid black screen and the idle whirring of the CPU fan.  What I have tried  I have tried the recovery mode boot up, but no luck (The log does greet "Welcome to Ubuntu 16.04 LTS!"). I tried out each option that seemed useful:   dpkg goes through the packages as advertised, but strangely enough it always locks up on some Braille package until I do Ctrl+C, at which moment it spouts some error messages and then I think throws me into the normal boot. failsafeX results in a similar situation to the normal boot: a black void. fsck says the single partition I have is a-ok. grub seems to get a bunch of stuff. Don't know if it searches locally or fetches from the internet. network didn't work I think.   I tried following  but couldn't do the sudo part because the filesystem was mounted as readonly. So I ran fsck which mounts as RW and tried again.   This time, after running apt-get autoremove it went through many packages (Setting up foobar (X.Y.ZubuntuN) ...), sometimes installing packages, which I assume is the usual behavior. One thing to note though is it kept getting stuck several times, so I had to Ctrl+C it out of processing the current package. It finally ended on "Processing was halted because there were too many errors.".  While  seems to mention some of the graphics problems I've been experiencing... I have Intel HD Graphics, not Nvidia. I'll keep looking into it.