Change File Transfer Settings
Windows

Screen Sharing with Full Control but No File Transfer

Give users full mouse and keyboard control while disabling file transfer access. Choose the method that matches your version.

Free Version

mouse Click the Show My PC button — a dialog with advanced permissions will appear.
check_box_outline_blank Uncheck the Allow Access to My Files checkbox.
play_circle Click Allow — the session will start with no file access.
Free Version File Access Dialog

Premium Version

settings Before starting the session, please go to Options > Settings.
check_box_outline_blank Uncheck Allow Remote Users to Transfer Files and click Save.
play_circle Click Share Screen to start the screen sharing session.
Premium Version File Access Settings