Microsoft Arc Touch Bluetooth Mouse and Windows 8.1 - Misleading notebook built-in Bluetooth adapter

The configuration:
-Sony Vaio Notebook (older edition)

-Windows 8.1

-Microsoft Arc Touch Bluetooth Mouse

Sony Vaio with Windows 8.1 can't recognise the Microsoft Arc Touch Bluetooth Mouse.
The built-in bluetooth adapter works fine, bacause it recognises e.g. cell phone with bluetooth or other bluetooth mouse.
Microsoft Arc Touch Bluetooth Mouse is compatible with Windows 8.1.
Where is the problem?

This Sony Vaio notebook was originally shipped with Windows 7, then was reinstalled to Windows 8.1.
(Anyway Windows 8.1 works fine with older Vaio.)

So it was neccesarry to buy a cheap Bluetooth 4.0 Micro USB adapter.
This solved the problem.

How to check your device to see if it's Bluetooth 4.0 enabled?

AltGr Key Doesn’t Work

If you need for special symbols with AltGr key and this function does not work, press Ctrl + Alt(on left side of the keyboard) and the special symbol's button.

Fedora 22 proxy settings

Yum:
sudo vi /etc/yum.conf
proxy=http://proxy.server.name:port

and if you need:
proxy_username=youruser
proxy_password=yourpassword

(If you define a proxy server in /etc/yum.conf, all users connect to the proxy server.)

dnf:
sudo vi /etc/dnf/dnf.conf
proxy=http://proxy.server.name:port

Yum Extender
Edit
Preferences
Yum
Proxy

Export:
export http_proxy=”http://proxy.server.name:port”
export ftp_proxy=”http://proxy.server.name:port”

Message if you want to change something in BIOS: View only item

When i wanted to change something in BIOS (e.g. boot order), always this message appeared:
View only item

It was neccessary to remove and replace CMOS battery (CR2032).
After replacing CMOS battery the "View only item" message was gone.