Deleting Flash Drive File

[Len613]

On my desktop computer I dragged my My Documents folder to my flash drive.
Then I wanted to delete a sensitive file from the folder in the flash drive only and did so.

But when I checked in the computer hard drive I found that the file had been deleted there also.

I went to the recycle bin and restored the deleted file.
But now my flash drive has lots of other files there that I did not put there.

I thought that deleting a file in the flash drive would delete it there only. How can I do this?

Why did so many files appear on the flash drive when I restored only one?

I am considering erasing the flash drive on my laptop which does not contain the sensitive file.

 

[kimsland]

On my desktop computer I dragged my My Documents folder to my flash drive.

That's a new one

Sounds as though you must have created a shortcut to your My Documents folder files
Plus, due to synchronization, anything removed from the flash drive also removed the file in your local My Documents
Next time, only copy\paste the files you actually want to store on your flash drive within My Documents folder

Also restoring files, seems to have restored many files in My Documents, being on the Flash Drive too (or worse -> only)

My documents should not be dragged anywhere
The specific contents, possibly yes (but My Documents carries many other common default files as well, coming from All Users profile too )