In order to delete files under the current share in User mode, the following conditions must be met:
The user is able to write to the share.
The user is able to write to the file. This can be for two reasons – the file is writable by everyone, or the user is a member of a group with write permissions for the file.
“Grant rename and delete privileges to non-owner of files” must be turned on in the Share Listing>Advanced Options tab.