Guest access besides Domain

[javaheryz]

Hi

I have shared two folders on a TS-231P (FW 4.3.3.0299), both having guest access set to full control. Before joining it to our AD domain, these folders where working fine (accessible from my domain-joined PC). After joining it to AD domain, upon double-clicking folders in Windows Explorer, it asks for credentials. I need both full control guest access and AD connection in this scenario. Both Windows ACL support and Advance Folder Permissions are turned off. I have tried granting full control access to local everyone group, Windows Everyone user/group via Windows Explorer (with Windows ACL support on) and my PC's machine account (for test), all without success. How can I do that?

Thanks in advance.