I tried searching the forums but couldn’t find anything about people having the same issue.
I downloaded the JME3-Alpha package and got JMonkeyPlatform from there. I am running it on Windows 7-64bit with JDK 6.23. For some reason every time I close JMP, it automatically reopens. Anyone else having this issue or know how to fix it? Its a great app and all but I don’t really want it running all the time 
Yeah, I heard of that issue once on windows, dont know how the guy fixed it, did you maybe interrupt an update jMP or did it fail? Maybe the update got stuck somehow and its restarting rather than shutting down because of that? Also, did you try every way of closing the app (not just via x button but also via the menu)?
I dont think so. I close it everyway possible and it still pops back up. I have to restart the machine if i really want to get it to not come up.
Maybe you can try starting it from command line, it should display the output of the launcher too.