Everything freezes, like the mouse freezes on the screen too? It may be the driver is not totally compatible with your system. Try install the driver in safe mode.

Do you get good signal on the computer? Is the 2.4Ghz or 5Ghz network slow? Try another computer maybe. Sometimes programs on the pc affects performance of the adapter

Range extender has the latest firmware? When it disconnects on your phone, do you check the IP address? If WiFi shows connected but not internet, no IP address, you may set static IP address for your...

Install the powerline scan utility. http://www.tp-link.fr/download/TL-WPA4220_V1.html#Utility Or set static IP on your computer, refer to http://www.tp-link.fr/faq-398.html

Is the extender too far away from your router? It's kinda normal that speed slows down with extender cuz it works in half duplex, cannot send signal to the router and your client at the same time....

English?