I have a mysterious problem:
One of the folders under Global is no longer accessible for everyone, even though Everyone has read rights in the file handler. The unauthorized user gets the EPiServer login. We use Forms authentication.
The other folders under Global works just fine like before.
I've tried to remove and reset the access right without any luck.
What version of CMS you are using? can you provide a complete stack trace of access denied error
Also check your web.config, look after location path="Global" and see if you have set any access rights there.