After putting the camera away for a few months, I have tried to bring it back to life. Worked fine before.

Switched on, battery shows power and plenty of room in memory, but it doesn't focus or won't take a picture. Unresponsive.

Is there a kill switch somewhere that I inadvertantly hit or something?

Thanks for any hints.

I don't have the d100, but on most cams I've looked at including my Coolpix, there is a "reset" to manufacturers settings in the menu. Usually when I get to this point, I do just that...reset to beginning and start anew. Also, check to make sure you haven't accidentally set it to manual focus. I discovered that with my wifes Pentax DSLR. I couldn't get it to do anything and she had to show me what I was doing wrong...hehe, considering she's been shooting a week and I've been shooting for several years....sheesh...did I feel dumb!!! Especially when my 7 year old granddaughter had to show me how to use a Nikon D50...hehe...Anyway, hope this helps...
Ken

I'd trya reset if hte menu works.
A friend I was shooting with at the F1 testing in Jerez reset her Nikon 3 times in the morning and twice in the afternoon. It seems normal practice to do the menu reset to defaults to clear up unexpected (in)action of her camera.

The reset function will only clear the custom settings back to original factory default, as far as I know.

The two problems may be related - if it's in "S" focus mode (on the front of the camera, about the 4:00 position to the lens when looking at the front) then the shutter won't fire if the lens isn't in focus. Try putting it on "C" or "M" to see if the shutter fires. If that fixes it, then maybe the lens contacts just need to be cleaned. These are the five or so (could be more) little round metal buttons that stick out of the black metal ring on the lens mount. I've never had to do this so I can't tell you for sure how it's done, but I think people use regular pencil erasers to do this (check the manual or call Nikon to be sure).

One other thing that fixes more problems than you'd believe - pull the battery out and give it a fresh charge. If it is full, just pull it out for a half hour and see if that does it.

Not sure what did it, but D-100 is back to life.

Recharged battery. Even though it showed plenty of juice before.

Reset settings.

And, noticed the control button (shooting mode button) was about 1/8 turn out of Manual. Perhaps it wasn't clicked in to Manual or I had just moved it changing battery or resetting.

Who knows.

Thanks for the suggestions.