I wanted to update my kubuntu form 17.10 to 18.04 and i found [this thread](https://askubuntu.com/questions/1029049/cannot-upgrade-to-kubuntu-18-04/1029209).

I used:

```
sudo update-manager -d

```

and it did something, but when I restarted only a black screen appears with the KDE PLASMA mouse cursor and a popup says:

> 
> could not start kdeinit5 check your installation
> 
> 
> 

with an OK Button

What I tried so far: `CTRL`+`ALT`+`F2` and login.

`inxi -F` says that is have Kubuntu 18.04. So that's what I wanted

```
sudo apt-get dist-upgrade

```

can't install libqt5xcbqpa5.

```
sudo apt-get --reinstall install plasma-desktop

```

any ideas?