When performing a Skim on a File System or on SharePoint content, correct permissions are critical. Even with access granted at the root level, the skim may fail with a verification error when trying to access child folders.
Cause
The Skim may fail when trying to access a child of a parent folder where it has insufficient permissions at the parent level, even if access is granted to the child folder.
Example
The example below illustrates such a situation for a file share index on the location \\Server\Share\Subfolder\Sub-Subfolder:
\\Server\Share - Authorised
\\Server\Share\Subfolder - Not Authorised
\\Server\Share\Subfolder\Sub-Subfolder - Authorised
In this instance the index cannot succeed because of the lack of rights in the parent location. It is a requirement of some of the Windows API methods that the FileShare Connector uses that access throughout the specified path is in place:
"If the string ends with a wildcard, period (.), or directory name, the user must have access permissions to the root and all subdirectories on the path."
https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-findfirstfilew
Resolution
Windows and SharePoint interfaces require that the Skimmer service be granted permissions throughout the entire folder hierarchy.