I've been using Ubuntu for quite some time now and I absolutely love it. I recently purchased a laptop (Dell Inspiron 15r 3542) which is supported by Ubuntu, and have pre-istalled ubuntu 12.04. So, it asked me to update to 14.04, and then.... After downloading packs it started to install them. Some time after it started there was fading electricity for 5 minutes and later i found DELL falled asleep. Now, i write this lines without any chance in update or next launch of my DELL. how to check update status without reboot? Window is just grey.
You should be able to press the power button to bring it out of slumber. If this does not work, you can usually do a hard power off by pressing the power button and holding it down until the computer shuts off.
If you need to, reinstall using a live CD or DVD.