Deepin Desktop not working on Arch linux

I installed Arch Linux properly and then I wanted to install Deepin Desktop so I can use it for working, browsing, etc. I did all the steps like installing it with

pacman -S deepin

, then changing some lines in the config file like this:

 vi /etc/lightdm/lightdm.conf

to change that line to:

greeter-session=lightdm-deepin-greeter

them enable lightdm via:

systemctl enable ligthdm

and then

unmount

so, normally, after a restart I should get to the LogIn screen of deepin, but the only thing it does at booting is an underscore blinking at the top-left corner. when I restart to the bootable usb stick to fix it, (like pacman -S deepin) I get a warning:

database file for '    core' does not exist, same for '    community' and     'extra'.

I used these tutorials and browsed the internet for a solution, but without result, so please help.

https://wiki.archlinux.org/index.php/Deepin_Desktop_Environment#Installation
http://www.jianshu.com/p/ee466d585f3e
https://www.google.at/amp/s/de.m.wikihow.com/Arch-Linux-installieren%3famp=1