By default, attachments and other files saved in Yesplan can only be accessed by people who have a Yesplan username and password. However, you can also make files accessible externally. In that case, everyone who has a link to the file can open the file without signing in to Yesplan first.
In “System Settings” > “Files” > “Files with External Access”, there is a list of all files that are accessible externally. You can turn off the external accessibility here. Files that are deleted from Yesplan will no longer be accessible, either internally or externally.