Updating PHP permissions to allow auto updates

Hi,

I haven’t been able to auto-update WordPress for a few versions now. I’ve been installing every update manually, but I want to be able to update with one click again. At the moment, just clicking update returns this error –

“The page cannot be displayed because an internal server error has occurred.”

I don’t have PHP error logs, so my host told me to alter the PHP permissions, with these guidlines –

“This is done through the “File Manager” – Websites >> Domain Name >> File Manager >> Right-Click on the file or folder in question >> Get Info >> You will want to give the “Anonymous Web user” and\or “Application pool identity account” write access to the file or folder.

The “Anonymous Web user” will allow a PHP application to write to the files\folders
The “Application pool identity account” allows an ASP.net application to write to the files\folders”

My issue here is that I don’t know which file or folder needs updated permissions? I assume it’s a .php file?

Thanks!