Problem with Nokia 500 fontzoomer.

I have a problem with my Nokia 500. I used fontzoomer lite (downloaded from ovi store) to change my device system fonts. It worked great(only some problems with symbols).in another way (which I found in a site); I copied font from my laptop' and renamed as in z:/resource/fonts/ and paste it in f:/resource/fonts/ and restart my device. It also worked, but now when i using fontzoomer to back to default fonts or any other fonts it is not working. It displays "do u want to apply changes? phone will be restarted(if required)." As I select yes device restarts but font remains the same. What should i do?
Help please!!!
