Sharing Folder causes to remove NETWORK SERVICE security

Assume that you have hosted your site folder in IIS..and you have gives NETWORK SERVICE security access to that folder.
If some case you share that folder for somebody..note that it's remove the NETWORK SERVICE security access from that folder..
if you will receive an error from IIS saying


HTTP Error 500.19 - Internal Server Error

The requested page cannot be accessed because the related configuration data for the page is invalid.

This because the IIS process can't access you folder.This is one of cause that raise this error..

cheers!