Open Tableau Desktop with administrator privileges by right-clicking on the icon for Tableau Desktop and selecting 'Run as administrator'. Then, attempt to connect again to the Excel file
If selecting Run as Administrator does not resolve the issue, completely uninstall and reinstall Tableau Desktop. Then, open Tableau Desktop with the 'Run as administrator option' selected.
Work with your IT team to ensure that your user account has administrator rights or security permissions to the AppData folder.
Work with your IT team to whitelist the temporary files folder in anti-virus or firewall programs that are in use.