Thanks for your reply. I have just resolved the issue this morning. It was the waterproof collar in the bulb holder….remove it and the bulb works. I simply trimmed back some of the collar - internal...

I have 2 E530 bulbs which I set up in house and they both work correctly. When I move them to their exterior positions neither bulb powers on. I am using Eiva IP65 bulb holders - I have confirmed...