package management - How to remove older version of OBS?

I have 2 versions of OBS in my Ubuntu 18.04 LTS.

One is OBS 21.0.2.-modified (or obs-studio --candidate), other is OBS studio 24.00.

The problem is when i installed the newer version, i didn't get just an upgrade from 21.0.2. to 24.00, i got TWO snaps at the same time.
Probably coz candidate version was in different branch of snap development or something.
Not a big deal, but...

The biggest problem is that now both versions can't work right and both miss some functionality.
For instance, 24.00 don't show up in tray (which is a life saver during busy broadcast).
Also when i chose OBS Studio icon (which is obviously 24.00, coz 21.02 was just "OBS"), only 24.00 version is launched! At that moment i can see how one version interfere with another in tray, which is hillarious).
I double checked what version is in tray, and it was exactly 24.00.

(What is weird, also, that built-in Ubuntu software manager can't see V24. Ubuntu Software center can't see it too. Snapcraft site by Canonical can't find it also. It can only be found by clicking direct link in Snapcraft but that's beside the point.)

Logical thing would be delete the old version in terminal BUT... when i use "sudo apt-get remove obs-studio", BOTH version are deleted.
When i use "sudo apt-get remove obs-studio 21.0.2-modified", or "sudo apt-get remove obs-studio --candidate", or just "sudo apt-get remove obs", Ubuntu can't understand the command or tell me that "OBS is not installed".
I used "purge" but with the same result.

I used snap managers like Stacer and Synaptic.

(I can clarify that OBS is a snap, you can see it for yourself - heresnapcraft.io/obs-studio and here (Stacer clearly shows OBS in a Snap category)

Also Synaptic surely works with OBS and shows both versions but calls it "packages".
picture of Synaptic showing me two versions
By snap manager i mean this one piece of software github.com/oguzhaninan/Stacer.)

First one can see nothing but 24.00.
Second one sees older version but somehow can only INSTALL it, but no unistall option!
When i try to use "uninstall completely" in Synaptic it can only see 24.00.

Using apt policy obs-studio i get this

apt policy obs-studio
obs-studio:
  Установлен: 24.0.0-0obsproject1~bionic
  Кандидат:   24.0.0-0obsproject1~bionic
  Таблица версий:
 *** 24.0.0-0obsproject1~bionic 500
        500 http://ppa.launchpad.net/obsproject/obs-studio/ubuntu bionic/main amd64 Packages
        100 /var/lib/dpkg/status
     21.0.2+dfsg1-1 500
        500 http://ru.archive.ubuntu.com/ubuntu bionic/universe amd64 Packages

Can i somehow erase the 21.02.-modified version? WITHOUT the complete removal and new install (coz there will be an incredible amount of work to create all the scenes and FX again).

(Note: I'm a total noob, i use Ubuntu coz i'm too tired of Windows, and everything is cool but this little problem).

grub2 - Lap wont boot after deleting windows7 partition

While I was using Ubuntu I accidently deleted the windows7 partition. When I rebooted I got the following error:

error:unknown file system,Entering rescue mode,grub rescue>

I've tried to reinstall Ubuntu, windows7 but the windows set up is loading files after that the windows logo is blinking forever,on Ubuntu-install Ubuntu option selected but system freezes.

"ls" command is used in the grub rescue> it results

the hard disk partitions as(hd0) (hd0,msdos15)...(hd0,msdos5)

apt - How can I solve Unable to lock the administration directory (/var/lib/dpkg/)

I am really New to UBUNTU 14.04 and whenever I try to update or install anything I get this error:

sudo apt-get update [sudo] password for trojanfm: 
E: Could not ge lock /var/lib/apt/lists/lock - open (11: Resource temporarily
unavailable)
E: Unable to lock directory /var/lib/apt/lists/ 
E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable) 
E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?

Will Wubi Ubuntu installer conflict with my current Grub Menu?

I have a desktop where I dual-boot Windows XP and Lubuntu. Given that Wubi makes use of Windows Boot Menu, If I install Ubuntu 12.04 from Wubi installer on Windows, will it be present on Grub Menu? Will there be any conflict between Wubi and Grub Menu?

No, it won't conflict but Wubi won't show up in Grub either. Wubi adds itself to the Win XP boot menu, so to boot Wubi the process would be:

1. Grub: Lubuntu or WinXP?


2. Choose WinXP


3. WinXP boot menu: WinXP or Wubi?


4. Choose Wubi
   (you may then get a Wubi grub menu asking you to choose a kernel, recovery mode, etc.)

startup - Howto enable boot messages in ubuntu 12.04?

Hello when I do reboot or init 6 in console under ubuntu 12.04 my system does not start correctly. it freezes in startup process.

Wow can I enable the boot-messages instead of the splash-screen.

Is this still valid for ubuntu 12.04?
How to enable boot messages to be printed on screen during boot up?

drivers - HP Color LaserJet MFP M277dw: previews and prints in colour instead of grayscale

This is my hardware/software configuration:

• HP Color LaserJet MFP M277dw


• HPLIP 3.15.11
  
  
  
  
  • Note of 6 Oct 2016: the problem persists with HPLIP 3.16.2
  
  


• HPP0053.PPD version 19.12, freshly updated last week.
  
  
  
  
  
  • Note of 6 Oct 2016: the driver is still the same
  
  

I want to print some pages from a pdf file with images in colour. I visualize this file with evince and want to print it in greyscale rather than in colour. Therefore, I activate the instruction to "print colour as gray" in the printer dialogue window.

In disregard of my settings, the preview of evince itself is in colour and so is the print. (Moreover, this occurs regardless of whether I set gray printing as default in the printer settings upstream of evince.)

This issue is recent is my computer. Previously there was a perfect correspondence between evince, its printer dialogue settings and the printer response.
Beside the regular Ubuntu updates, the only change that I can obviously connect this new situation to is the driver upgrade from HPP00036.PPD v 19.10 to HPP0053.PPD v 19.12.

This issue is not new to HP printers, though. This post suggests to add the same printer once again, but this does not work for me. I get a responsive colour/greyscale toggle only if I install my printer as a M577 model instead of M277 (thereby giving in the duplex printing capabilities). This indicates that the glitch has to do with the driver devised for this specific model.

In the internet it's possible to find similar complaints on HP printers in Windows environments as well.

I would like to restore a normal state of affairs.

• Has anyone had a similar experience?


• Is the HP driver the actual culprit?



• Is there a proven solution strategy to fix this?

Addendum 11/12/15

The screenshot below shows the job attributes of one print that I intended to print in grayscale and was printed in colour instead. The line `HPPJLColorAsGray yes' is apparent. Even worse, the document is printed in high resolution, ignoring the EconoMode setting too.

• Does anyone spot a fault that could invalidate these settings?

This is actually a workaround. If I add the existing printer HP Color LaserJet MFP M277dw once again as a new device and then claim that it is a Color LaserJet MFP M476, I obtain an interface enabling duplex printing and with a responsive colour/greyscale toggle. Not so for (some) other drivers of the same family, inclusive the very M277 as seen.

Also, it was interesting to observe that the driver for MFP 577 is still being recommended for a MFP M277 gadget. So one would be induced to oversee the driver for M277 that does exist, however glitchy, down the list.

In order to add a new printer (Ubuntu 14.04), go to System Settings -> Hardware/Printers and click on the Add button at the top left of the menu bar.

In my case the printer was already on and connected via the USB port. It might take a little time before the system scan the devices connected. Then the printer got recognized with its own true name. The rest is intuitive. The point of choice is a few steps later when you select the driver that actually works via the model name.

repository - How to add ppa repositories?

I always like to have my programs up to date but in ubuntu software center the software aren't always up to date.
I know about repositorys and i'd like to add some so how can i find the repository of certain programs in launchpad.
I'm using Ubuntu 12.04.1.

You can add a PPA location with the command

sudo add-apt-repository ppa:

For example sudo add-apt-repository ppa:gnome-desktop

You can find some help on Ubuntu Documentation