Anyone have experience with sample saving?!

Hello! I keep having an issue when it comes to saving my samples. I save them on my external hard drive, and at first they save just fine. Then couple days later i go back & it says it cant find my sample. Which is frustrating because it says it’s on my c drive even though my preferences are set through my E drive. Then i go to locate it & they don’t show up, even though when im out of the maschine program i can find them just fine. Then when i click the file through my file explorer it still says it’s still missing. Hopefully this makes sense, and i would be extremely grateful if someone can help solve this issue.