I understand the warning, but I don’t see where you can close an existing program in the IDE.
To date, I’ve been closing Mbed Studo, moving the program location, and then opening the IDE so that it cannot find it. Is there a button for closing an existing program that I’m not seeing?
you probably set or made (by moving the files) wrong Workspace because it looks like you have a Program folder as the Workspace. So you need to change the Workspace (should it be a parent folder where your Mbed programs are stored) via File-> Open Workspace...
I do not have more ideas without more information or printscreen of the project tree.
About reisntallation of MbedStudio. Of course you can reinstall it. Just copy this link and fill requested version at the end - https://studio.mbed.com/installers/latest/win/MbedStudio-X.X.X.exe
For example - https://studio.mbed.com/installers/latest/win/MbedStudio-1.3.0.exe