System.UnauthorizedAccessException:“Access to the path 'D:\Config.Msi' is denied.”

This error message indicates that the user or process attempting to access the file or directory "Config.Msi" on the D drive does not have the necessary permissions to do so. This could be due to various reasons such as the file or directory being locked by another process, insufficient permissions for the user account, or the file or directory being marked as read-only. To resolve this issue, the user or process needs to be granted the necessary permissions to access the file or directory, or the file or directory needs to be unlocked or made writable.