I recently upgraded my Windows 10 from 1803 to the latest 1903. Now Arduino IDE stars showing initializing, then Preparing boards briefly and that's it. I can't seem to get it to run. I'm trying to run Arduino 1.8.10 for windows. It didn't specify if it was 32 or 64 bit. I'm running 64bit OS Windows 10, version 1903. Java is loaded and running fine.
Any thoughts on what happening.
Are you running the APP version or the INSTALL version ?
The most common known cause of the symptoms to see are an over aggressive antivirus or lack of user privileges.
If it is Antivirus you should add the install locations to the exceptions / white list of your additional security.
Bob.
In Windows, you can run the IDE on debug mode. Maybe that will reveal something?
Open a command prompt and run (from the head) c:\program files (x86)\arduino\arduino-debug.exe.