Why won't my Nikon D90 Pop up flash button work?

The flash is fully functional because it works fine in any auto mode. However, when I put the camera into any of the four manual modes, the flash button doesn't work when I press it to pop the flash up.

Is there a certain setting that I should set my camera to for it to work?
Also, my camera won't communicate with an SB-600 when I try to put it into commander mode and set up the channels and everything correctly.

I sent my camera to the Nikon care center a few weeks ago and they sent it back saying that they fixed everything, but this problem has arisen again.

If your pop-up flash work with auto mode and it's not working in commander mode I'm pretty sure you're doing something wrong somewhere along the setting.

Put new battery in your flash. If the sb600 work like the sb800, set up the sb600 to remote, make sure the trigger is facing the camera.

Set the camera to manuel.
Set your pop-up flash to commander mode, adjust is power to "---" then adjust the setting for the sb600 to ttl, make sure you put the same channel.

pull up the popup flash.

Make sure you're using the front curtain.
Use 1/200 or lower speed, unless you have enable the fast sync mode.

Aim at something with the sb600 then take a picture to see if it's working.

Did the flash pop up when it was returned from Nikon? They probably have a 90 day warranty on any work they did.

First, try to do a complete reset of your camera to make sure you didn't set up something wrong.

You have to do both a reset as described on page 75, and on page 172. The first reset is for the general settings and the second reset is for the custom settings.

To use commander mode for remote SB-600, you must pop up the flash. Also when you change the mode make sure you depress the OK button. I always forget to do that.

The D90 is easy to setup for commander mode, the SB-600 is a bit tricky. So I would suspect the SB-600 is not setup right before I would the D90. You have to set the SB-600 to remote mode.

I do this all the time as I have a D90, along with a SB-600 and two SB-R200s. So I can confirm they are compatible.

http://www.althephoto.com