[Linux] Printer is Paused

Today got a weird problem with my HP printer. It would say that the Printer is paused.

After searching a bit found out that this is because the printer driver (cups) gets paused due to any printer error. In my case it was due to the paper jam.

The solution is quite simple.

1. Go to http://localhost:631/

This will open the cups maintenance page. If a password is asked, give your login password which has root rights.

  

2. Click on printers tab.  You will see your printer listed and in paused state.

 3. Click on the printer and go to the dropdown for 'Maintenance' and click on 'resume'.

4. You will see the following kind of screen and when you click on printer again, you will see that status has changed from 'paused' to 'idle'.

Ubuntu no sound fix for USB audio

Update 14/08/2012 - please see Edit2 below for a solution. 

Ubuntu 11.10 seems to be quite a step back in terms of usability. Things which worked in 10 are broken now. One of the things that was driving me crazy was the audio was not working sometimes.

My system uses a USB audio system (Bose Companion 5). I believe this issue is there on other systems using USB audio also.

When I used to boot, the system would come up but there was no audio. The audio would start once I would slide the volume slider down and up. But if I start VLC video player, the sound would go away all together and the only way it would work was to reboot the system. This was nuts.

After a lot of searching, i finally got the solution from Ubuntu Forums . Here's the relevant part of the solution.It involves un-installing and re-installing the audio systems.

Open a terminal and enter the following:

sudo apt-get remove --purge alsa-base
sudo apt-get remove --purge pulseaudio
sudo apt-get clean && sudo apt-get autoremove
sudo apt-get install alsa-base
sudo apt-get install pulseaudio

For some reason while removing alsa-base it removes the ubuntu-desktop. So you need to install it again.

sudo apt-get install ubuntu-desktop

Now reboot your system. Once it comes up you will see that the audio icon on the top bar is no longer there. But now all sound should be working without fiddling around.

Drop me a comment if you had this problem and this change worked for you.

Edit: Seems there is still some reboot issue as pointed out by Albin in the comments below. Once you reboot - you will need to go to Settings -> Sound and slide the volume indicator up and down to get the sound. :(

Edit 2 : 14/Aug/2012

I entered a bug for this as I got frustrated. And then after googling extensively I finally got a solution of setting usb audio as primary sound device and it seems to work.

Essentially you need to do the following steps :


1. Edit the file /etc/modprobe.d/alsa-base.conf . Since this is a system file you will need to sudo to get this done. e.g. 

$sudo vim /etc/modprobe.d/alsa-base.conf

2. Scroll down to the end. Now you have to change the line which says 

options snd-usb-audio index=-2

to 

options snd-usb-audio index=-1

Reboot and it should work. 

Ubuntu - getting it to show partitions

One of the main frustrations that I have with Ubuntu nowdays , apart from the USB audio problem and the grouping of open windows problem, is that it has stopped listing the windows partitions that I can mount. I do not know who is the Product Manager, but he/she has their heads in a jar.

This blog post is a howto to undo that harm for the people who dual boot.

Fixing the problem of partitions not showing up ( see the rectangular area for what I am talking about)

The solution, it turns out, is quite simple. You need to use the Advanced Setting application to turn the slider to on as in the image below. You can achieve the same thing by using the udisks command from the command prompt also if you want, but I am not gonna talk about that here.

Toggle this option!

Once you toggle this switch, the partitions will be shown in the bar on the left side. however, you will still need to click them to mount them - which is fine with me as I do not want to mount all of them.

Install the advanced setting using Ubuntu Software Center or Synaptic.

In case you do not find the advanced settings, you will have to find it in the Ubuntu Software Installer and install it. I do not know why this is not installed by default.

Redmine Ubuntu Installation Error

One of the most amazing software tools that I have found which meet almost all my needs in the day to day working is Redmine (hard to convince people in the office though). However I ran into a problem recently which seems to be quite prevalent going by the searches thrown up.

Cannot start Ruby on Rails application

The directory "/usr/share" does not appear to be a valid Ruby on Rails application root.

Dreaded Error

Since I had installed it earlier on  a VirtualBox image running Ubuntu, i was quite taken aback. Google searches throw up that people have a lot of problems but the solution was not really forthcoming. I knew that the solution was some small error, but I could not put a fix on it. So, I looked at it again ... and the error was quite small ... wrong directory linkage 

From the install steps 

sudo ln -s /usr/share/redmine/public /var/www/redmine

But i had forgotten the /public and was doing

sudo ln -s /usr/share/redmine/ /var/www/redmine

So, if you are getting this error - and a lot of people are - make sure that you are linking the correct directory. I suppose this will be the case with other Ruby applications also.

Other resources:

• Redmine 
• Installation instructions for Ubuntu
• Bitnami Redmine for a hassle free installation on Windows

Show me the apps !

Somedays, i just love the new interface in Ubuntu unity. This is one of them. The 'Windows'+ W key combination shows me all the running apps ont he desktop neatly arranged. Then just click on the app you want to go to. This is much better than using the Alt+Tab combination to cycle through applications if you have many of them open.

missing org.eclipse.wst.sse.core

If you get this error with Eclipse on ubuntu, this is how you solve it. This is because of faulty default apt-get repository for Eclipse. You will most likely get this error when you are trying to install the ADT for Android development.

Help -> Install New Software ... 

There add the following source

http://download.eclipse.org/releases/indigo/

My current Eclipse install is indigo - which you can find from the splashscreen. To make sure that the URL exists , just open the url you think you should be using in Firefox and it should not give a 404 error.

Now you should be good to go. Go to the 'Install Software..' and try installing the ADT plug-in again - it should work now.

/Rant
Linux is supposed  to be a dev friendly environment, but the amount of time I spend getting things to work after every new upgrade to the system is insane. No wonders Linux is still not capturing the market ( apart from being a lousy platform for games).

Screen Resolution problems on Ubuntu ?

Did you just do an upgrade in Ubuntu, and are now stuck with a 640x480 resolution ?

This seems like a common problem on machines with Nvidia based graphics cards. There are various solutions given on the net, but the one that works for me ... remove the Xorg.conf file.

Heres how you do it.
1. Start up your linux.
2. press the keys together : ctrl+alt+F1 . This will bring you to the command prompt.
3. Login with your username which has admin privilidges.
4. mv the Xorg.conf file to something . E.g. I used the following :
sudo mv /etc/X11/Xorg.conf /etc/X11/Xorg.bk
5. go back to the UI screen by pressing ctrl+alt+F7 .
6. press ctrl+alt+backspace to restart the X server.

presto , it will recreate the Xorg.conf file and you should be back to optimal resolution now.

If you run into issues, you can go back to the F1 screen, and mv the backup back to the original filename. And try your luck on google.