Check if anyone has been cleaning the lampshade most people hold the duster still and turn the shade, this revolves the shade and lampholder and can twist the wiring in the lampholder pulling it out of the connections. If the wiring is old, the insulation on the wires can crack, and fall off, twisting the bare wires together and shorting them out
ALsnr
September 2009
Sounds like the switch is connecting live and neutral, causing a short circuit.
When did it start doing this?
Did you do anything that might have caused this?
You don't mention having done (or had someone else doing) any work to the electrical system - have you? If so, what?
Adam
September 2009
You have probably made a wiring error at a ceiling rose or junction. This typically happens when you connect the switched live that comes back from the switch to neutral instead of to the lamp positive.
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