I faced a similar problem and also thought it could be what Manta said, but unfortunately not.
I was able to get 4 flood lights and an "open" sign working in my self built warehouse (10x10) that has two floors. For the first day I was able to get everything working. Once I turned on the generator, all the lights went on and stayed on for the whole night. But two (game) days later, nothing worked, even though the generator was full of gas and showed that it was providing electricity to 5 lights. I thought It was a light bulb issue, but when I right click on the flood lights or the open sign, I don't get any choices to remove light bulb like I did in the past. Its really, really frustrating, because its really dark and hard to use the warehouse...and also because the problem is now extending to any lamp in any house that I find. If I go to a random house and try to use a lamp, I no longer see the choice to remove lightbulb or turn it on. I just can't seem to find the lamp, no matter where I right click. I can disassemble it, though. And I can pick it up. Also, FYI, regular light switches work and I can still move the flood light to different locations but they still won't give me access to them. We are on a private B41 Multiplayer, with three mods: Skill Journal, Hydracraft and container manager). Even the host of the server is seeing the same issue now. Help!