How do I remove an installed .pkg file I recently installed this "CH341 Driver" so that I could connect my new chinese Arduino. 

But when I plug the USB cable, connected to the Arduino, into my computer it crashes immediately. A few moments later a message pops up that tells me that, because of a problem, the computer had to restart. 

Now I want to delete this installed driver and download another driver or another version of it. But in order to do so I need to delete the old software (which makes my computer crash). 

I looked around on the internet about how to do so, but most of the googled suggestions tell me that I can simply remove it from the "Applications" folder. It isn't a program so that won't help. I also found a few results that tell me to open terminal, enter the command "pkgutil --pkgs", search for the package and enter the command "sudo pkgutil --forget the-package-name.pkg". 

But I can't find the package name in the list. So I went to "About this Mac" -> "System Report..." -> "Software" -> "Installations" and there I can see the names of the packages, but unfortunately I can't remove them from there.

So is there anybody who can tell me where I can remove them?
You can check what was installed and remove it manually. Copy the *.pkg file to some empty tmp folder. Then:

xar -xf YOUPACKAGE.pkg


Then print the content of the Bom file with:

 lsbom $(find . -name Bom)


You'll have the list of files like: (Here's the part for Cisco AnyConnect)

./opt/cisco/vpn 40755   0/0
./opt/cisco/vpn/bin 40755   0/0


All file path start with . but they are installed relative to the root folder (/). In my example I have to remove /opt/cisco folder.