Library problems

I lost songs in my main collection and wanted to add them again. I made a temporary engine prepare folder on the desktop of my computer. Took the songs and draged them to the right folder in engine prime 1.3.1. All 78 was analysed. BUT when i emptied my engine prepare folder they went missing?! Shouldn’t they end up in engine Library?! Please help here. Why is not my songs being copied to engine library anymore?

Engine Prime is a database management software. Any entries you make to the database will reference to the source folder. In your case, if you added the music files to an engine Prime crate it doesn’t mean the files will be copied to a folder with the name of your crate. They will still remain in your “prepare” folder. Deleting the “prepare” folder leads to invalid reference in Engine Prime database. If you lost some music files and still know the folder where they were located originally, you can put them there and allow them to reappear in your library.