XF 2.2 I can't Install any styles to the Xenforo 2.2


New member
I just recently upgraded to 2.2.1. Since there are problems with the current theme, I wanted to install a new one. I have tried install 4 different styles but it didn't work. I have tried it with various ways.

I have upload style files into the src/styles and import XML.
I have tried install .zip file to directly from the ACP.

In every attempt I am getting this error:
Please upload a valid style XML or archive file.

All add-ons already disabled.