Ubuntu Howto’s Gotcha’s and assorted Recovery actions

Here is a set of Ubuntu Howto’s that have dug me out of the clag on many occasions. Linux/Ubuntu is by far the best operating system and software suite out there. Yet few use it as a day-to-day operating system. They should. It’s wonderful. Sometimes though even with the best of tools there come times when things go wrong. That’s what these posts are here for. (alphabetical order)


Audio

Here’s a fix to a problem I had with Audacity and getting the microphone to work properly. Audacity in-built Microphone Problems on Ubuntu – fix


Bluetooth

I had a annoying road block trying to transfer files from my Android phone to my Ubuntu laptop. Everything works seemlessly going the other way but not from phone to PC. I found a ludicrously simply solution:

Bluetooth File Transfer Problems from Phone to Ubuntu? A Quick Fix

Then I went swimming with my phone in my pocket and had to buy another one. This next post covers a full set up (with gotcha’s) with screen-shots using a phone that has never been connected to the Ubuntu box before.

Transfer Files to Ubuntu with Bluetooth? Here’s How


Desktop

Lost the location of that really nice image you are using for the Desktop background? Here’s how to find it. Find Ubuntu Desktop background Image

How to Start or Stop the Gnome Desktop and switch between it and TTYs. Gnome Desktop Stop Start and Access TTY’s


File System

Ever had a file that you simply could not delete? Even by Root?. It’s called an immutable file. Here’s how you get rid of the thing . Deleting Files that won’t Delete in Linux.


Gimp/Image

I had a problem blowing up a low resolution image and getting it centered. Here is the simple way to do it. Gimp Print Centering. Here’s How

My sister-in-law presented me with a pile of HEIC image files she had taken on her Apple phone that needed to be converted to JPG’s. Here’s how I converted them into JPGs (and PNGs too) using a command line tool available on Ubuntu 18.04. Converting HEIC files to JPG or PNG on Ubuntu 18.04


Kernel Panic

I have an old HP Compaq DC5800 that used to happily run Ubuntu 16.04LTS but Kernel Panicked whenever I tried to update the Kernel beyond version 4.13.0-45-generic. The problem came down to the BIOS level on the PC. Here’s the fix: HP Compaq DC5800 Kernel Panic on Ubuntu: Fix


Memory/Storage Issues

I cocked up once when I was doing a back up of my hard-drive. I ended up with a Readonly file system. Here’s how I fixed it. Ubuntu: Fixing a Readonly Filesystem.

So what exactly is the memory fitted in your Ubuntu box? How fast is it and how much of it is there? Have you got any empty expansion slots? Here’s how to find it all out. Ubuntu: What memory is fitted to my PC?

Sometimes a USB stick or drive simply won’t auto-mount. Here’s how to do it manually Linux: Mounting a USB Drive Manually


MySql MariaDB

The primary database is MySQL which is being slowly replaced by MariaDB. What applies to MySQL almost always works for MariaDB. In fact I have never found otherwise.

So what do you do when you have lost the root password to the database? Here’s how to fix it. MySQL or MariaDB: Lost Root Password Resetting

If that is not enough here is a later and more comprehensive version – because I DID IT AGAIN. This time on Ubuntu 20.04 Lost Root Password to Mysql and Phpmyadmin

What do you need to do to get the database to start on boot? Or maybe you want to stop it starting boot. Here’s how. Ubuntu: start or stop MySql and Apache2 on boot


Opera

Can’t get videos to play on the Opera browser on Ubuntu? Here’s a simple fix. Opera on Ubuntu 18.04 and 16.04 won’t play videos – Simple Fix


Package Manager problems

I managed to corrupt the package files and/or the status file so couldn’t do any new updates and ended up with a warning icon in the task bar. This is how I recovered the situation:

Ubuntu Error: Opening The Cache: Fix


Processor Overload with YouTube Videos

I’ve got a bad problem on Ubuntu 18.04 where playing YouTube (or other) streaming video eventually causes a processor overload. Here is a work-round. If I ever get a proper fix I’ll put it up here as well.

Processor overload with YouTube Videos (Ubuntu 18.04)


RhythmBox

I had a problem with RhythmBox where it was not seeing newly added music. It came down to a corruption of an xml file. Here’s the fix. Is RhythmBox Missing Music Files? Here’s a Simple Fix


Snap Package Font Issues

After I upgraded to Ubuntu 20.04 I went over to using a snap package for FreeCAD (among others) and tripped over a nasty Gotcha with accessing the system fonts. I believe other snap packages suffer similar problems. Here’s what I did: FreeCAD Snap Package Font Problem: Fix


Video

Here’s some Ubuntu howto’s for converting/reducing video file size.

So first off, here is how to change the format of a video file. (valid to Ubuntu 16.04 only). How to Convert video file format (Obsolete). (** This conversion process is now obsolete. In Ubuntu 18.04 avconv is no longer available. Use winff instead **)

Getting the video file as small as possible without significantly losing quality is a must. Especially if you want to self host a video file on your website. Here’s how. Reducing Video File Size


VLC Issues on Ubuntu 22.04

I couldn’t get VLC to display either the integrated camera or a USB camera on Ubuntu 22.04. It came down to the need to do a little more set up as VLC was installed as a snap package. Here’s what I did: VLC On Ubuntu 22.04 Viewing Webcams Fix


WiFi

What do you do if your wifi connection goes AWOL? Here’s what I did with mine. Ubuntu: Wifi connection has gone missing?