No stars seen

Pretty obvious, but:

• Are the dome and mirror petals open?
• Is the dome in the correct position?
• Also check that the dome is not set to manual on the lower row of buttons on the central section of the control desk.
• Is it cloudy?
• Are the position and equinox in the TCS correct?
• If you're using the TV have you typed TV ON on the ICS to put the TV flat in, and is the camera turned on?
• If you're using the CCD, not the TV, does the shutter open and close - check the Mimic?