code Igniter shows ‘Disallowed Key Characters’

Before fetching an url CI check the POST , GET and others ( SERVER,COOKIE, ENV) global variables.

If any name value pair contains some special character ( except A-Za-z_ etc) in name part then CI show ‘Disallowed Key Characters’ error.

so, if you want to access any url with product%name=3c as POST values it will generate an ‘disallowed key characters’ error.

But if you pass ‘ productname=3c% ‘ as POST values CI will not catch thsi error.

You will get hint of this in system/libraries/input.php file on function _sanitize_globals().