Nobody can tell you anything without proper system info or other technical details. From panels not rendering their labeling properly to language issues to specific fonts genuinely being missing this could be anything. you need to be much more precise and provide as much info as you can.
Running windows 10 which I recently downloaded. It's working fine with everything on my PC. My pc acer i5 cpu 16 memory Nividia geoforce GTX550Ti
I'm just learning AE so not sure of certain terms etc... I currently have about 600 fonts on my pc could this be a problem?