Changed File name, now sketch won't open!

Hello,
I changed the filename on my senior design project yesterday to reflect it was the most recent copy and now it says "Could not create the sketch". I tried to change it back but I'm not sure if I renamed it exactly as it was. Please help!
-Ben

How did you change the name ?
Is the program in a folder with exactly the same name as the program ?
What exactly is the filename now ?

Found the proper syntax in the appData/local preferences and matched the names. Problem solved. Thanks for such a quick response!

It is not "intuitively obvious to the most casual of observers" (except in hindsight and poking around) that the filename of the sketch must exactly match the folder name it is in (and the IDE sort of hides the facts from you when you are looking).