Question: I installed TeamTalk from <http://bearwear.dk> inside my home directory, but when I try to run  `./tt5srv -wizard` I get

```
error while loading shared libraries: bdl.so.2: cannot open shared object file: No such file or directory

```

I tried with and without `sudo`

I found fixes for other libraries but I didn't see any mention of bdl.so.2.

Ubuntu 18.04. How to fix this? Is it another case of wrong location or symlink?

Answer: 
Mysql 5.7 is not available to the Ubuntu 20.04. Only mysql 8.0 and higher version are available to Ubuntu 20.04 when you use mysql repository. Here you are using bionic source list (Ubuntu 18.04) for Ubuntu 20.04. I believe this workaround sometimes causes messup with dependencies tree.

You need to download mysql 5.7 packages with their dependencies from [official mysql site here](https://dev.mysql.com/downloads/mysql/5.7.html) and install manually by executing below command in terminal.

```
sudo dpkg -i <package name>

```
The later error `mysql-community-server : Depends: mysql-client (= 5.7.31-1ubuntu18.04) but 8.0.20-0ubuntu0.20.04.1 is to be installed` is occurred because of multiple versions of MySQL available. When you tried to install mysql-community-server 5.7, APT tried to fetch latest mysql-client which is 8.0 since all have same priority and that's incompatible with MySQL 5.7.

Though installing packages one by one using DPKG as mentioned by [other answer](https://askubuntu.com/a/1260766/1107512) is fine but that may be long manual task.

To make APT fetch mysql-client 5.7, consider changing priorities. To do that run

```
sudoedit /etc/apt/preferences.d/mysql

```

and add

```
Package: mysql-server
Pin: version 5.7*
Pin-Priority: 1001

Package: mysql-client
Pin: version 5.7*
Pin-Priority: 1001

```

Retry installation process. `sudo apt install mysql-server` should now fetch 5.7 by default.