NO CAD PROGRAMS WORK!!! WHY??!! PLEASE HELP ME!!!

I have PTC  ProDESKTOP, this isnt working as it says i need o run the startup again and it wasnt installed correctly but i do not have the start up. it was installed correctly as i have been using it for a long time with no problems.
so i downloaded an other CAD program but it didnt work, i re downloaded it, it still didnt work. i went on a different web site and downloaded a different CAD program, it didnt work. i dont this for 4 programs and none work. they all do the same thing!
 
they download fine, open fine but when i go to draw on the empty screen it stays empty... nothing comes up, no line no circle i can not draw anything on it! i am drawing something as wen i scroll over it a hand comes up or something to grab an move it, but i can not see anything.
have i got a bug? a changed setting? a virus? a broken chip? i have no idea, please help me!
i will appreciate any reply.
thank you for reading

Most CAD programs are not just a pick-and-go piece of software. They need some configuration, may require some specific graphics features/hardware, etc. This is why CAD programs are sold and implemented by authorized partners. Your CAD reseller will be happy to help you installing your CAD software.

i can understand this but why would all of the other CAD programs of worked until i certain point when all the programs i downloaded stopped working?
thank you for your interest and help