Nikon D80 Camera Flash Fault?

Suddenly my Nikon D80 digital SLR does not do flash anymore. The flash unit is built-in. If light levels are low the flash unit pops up, and a small white light shows (this is for auto-focusing I guess). But if the shutter programme shows a flash symbol the shutter will not activate. If the shutter programme does not show a flash symbol then the shutter activates as normal. I guess the flash bulb might have burnt out, or is there a secret setting that might turn the flash back on?

Pop the flash up & try to fire it in manual mode. If you still get no flash firing, then it's likely the flash tube is burnt out (the D80 is an older model, and it's possible that either you or a previous user have used the flash enoguh to burn it out).

The doesn't render the camera useless though! If you still need flash, invest in an external speedlight (either a Nikon, or plenty of choice of cheaper manual flashes).In fact, most external flashes will be better than the pop-up as you can swivel/bounce them or use them off camera.

Onboard flash gives a harsh, on axis light. Getting the flash off camera alows you to change its direction & modify it.

Most likely your flash has a mechanical or electrical problem. Nikon flashes sometimes pop a mechanical linkage which is easily fixed by anyone with a bit of mechanical adeptness. You can search for "D40 flash repair" to see tutorials on how to fix this. Electrical problems are best solved by getting an external flash. Even a SB400 will be much better than the built in flash and is cheaper than getting your camera repaired.