Users can have the following permissions:
Login - the right permission to log in to the application. Without it, the user cannot log in.
Send packages - the right permission to send packages. Without it, the user cannot send new packages.
Public - the permission to send public packages.
Internal - the permission to send internal packages.
Private - the permission to send private packages.
Receive packages - the right permission to receive packages. Without it, the user cannot receive packages (packages cannot be addressed to him).
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Download files without login password - the permission to download package files without reentering the login password. Without it, the user must reenter his login password before each download. Users from ADFS cannot have this permission revoked, because they log in outside of the application.
Newly created users have the permissions set according to Settings - Configuration - User default settings. The administrator can modify them afterwards, if needed.