Solutions I've tried: -Uninstalling and reinstalling under C drive.
-Signing out of Creative Cloud while it was trying to validate, would then give me licensing prompt, signed into Adobe ID with photography subscription, after the window saying, hit continue to use licensed software with the correct Adobe ID signed in, it went back to the endless validation loop.
What happens if the condition is true, but it becomes false somewhere in the middle of the loop body? It doesn't, because the computer continues executing the body of the loop until it gets to the end.
=( But, this part not so: /* Enter the temperature in Celsius: -300 Enter the temperature in Celsius: -500 Enter the temperature in Celsius: */ As you can see it basically does what I want on the math side, but I have no idea how to insert an error message to the do while loop.
These extra hidden characters are what is messing with your input and spawning the infinite while loop.