Tools - Settings - View - Drives -
Tab Select drive

Under "Tools → Settings → View → Drives" in the tab "Select drive" the following settings define the behavior after a drive is changed.

Show with drive select

This setting specifies which folder is opened when the drive is changed (by clicking a drive). One of three options can be chosen:

Message - if not ready

If this setting is checked, a message appears if the selected drive is not ready (e.g. no CD is inserted).