My Nokia N93 wasn't auto focusing any more. To resolve this you need to do a hard reset.
Here's how.
WITH SIM CARD:
*#7073# [ Green Call Key]
WITHOUT SIM CARD:
Hold down:
- * button
- 3 key
- Green ‘answer call key’
Then whilst all these are held down, press the power button and hold until the ‘Nokia hand shake’ displays, then let go of all of them.