So I was recently asked to work on a Pokemon game and I have been working on it quite a lot, but a little bit ago I was going to try and playtest the game - but it said "Failure to Create Process" and shut off.

I playtested it this morning and it worked fine. I didn't have internet so I reset my computer to a couple days ago to fix it and I had to redownload RPG Maker XP.

I tested all of the suggested things to do and none of them worked. I then tried making a new game without the Pokemon Essentials Starter Kit and it let me playtest it. I check to see if I was missing any files and I wasn't. I looked and nothing was wrong.

What do I do?

I don't know the Pokemon Starter Kit, but I assume the scripts are calling Windows API functions. Are you sure that all the required DLLs are here ?

Yeah. I double checked with a brand new kit and assumed that it would have all the required scripts. I then redownloaded it and copied all scripts to the broken one... it still won't work.