My phone's camera app doesn't work When I'm trying to take photos, I get the error:
The application Camera (process com.android.camera) has stopped unexpectedly. Please try again.

My phone is a Verzo Kinzo with Android version 2.2.
Factory reset didn't solve it.
What else should I do?
This can occur when you have insufficient storage available.

If you camera saves pictures to the SD card and your SD card is full (or does not have enough space for a new picture) it can crash.
A factory reset does not affect external storage.

Check where your camera stores it's pictures and if there is room left for pictures.