https://m.reddit.com/r/raspberry_pi/comments/1mxq4d/nexxtech_class_10_8_gb_sd_card/

Its possible your SD card isn’t supported. I use a sandisk ultra microsd myself and have had no problems.

You can also just start with a fresh SD image and remove the emulators you don’t want from the /opt folder with sudo rm -R /theemulatoryoudontwant

I find starting with the SD image easiest. You may want to test with another SD card if at all possible just to narrow that down as the issue.