i find gentle tapping with a screwdriver handle loosens them if not turn of
at the mains and smack it with a hammer

loz

wrote in message
...
I have a new simple/basic ceiling light fitting which I need to remove
and fit a another.
It is a plastic "cover" 4 inch across and a bit lees than an inch
deep.With the bulb holder in the centre.
There are no visible screws.I tried ,by hand,to unscrew it - but it
would not move .I also tried to lever (gently) it off the ceiling but
it did not want to move.
How does it come off ? Thanks in advance for any hints.