A nightmare of a refund

I bought a usb to hdmi converter from PC international. It was not compatible with my windows. I brought it back the next day for either an exchange or a refund. The device which is supposed to be plug and play ended up having to install drivers. They said they would install the driver. This ended up *******ing my windows. I had no time and needed my laptop for an important presentation. It did not seem to bother them and they did not understand the ramifications of the situation they put me in. In a country that customer service is the differentiating factor between companies PC Internstional will not get myself or my Companies support anymore.