Access to shared folder " \\****** " is denied.

I’m having an issue which with the Sonos controller not reading my audio files from my NAS drives; I have had no issue with this until the most recent update version 13.2. Looking on this forum and the wider internet there is clearly been a number of instances of this happening in the past.

So after painstakingly going through as many forum responses as I can I’ve tried the following to no avail:

Removed said folder from Sonos app and tried re-mapping to the library (this is where I’m now stuck as the Sonos App will not allow the folder to be added due to Access to shared folder is denied message)

Restarted everything - Laptop, Router, NAS multiple times.

Turned off firewalls on all devices still no change.

Changed permissions of various folders to allow full access from anywhere, again no change.

Opened a number of Ports on my PC/Router which where suggested by the Sonos help FAQ’s, no change.

Ensured my computer had the correct NODE type set up (it does).

Checked the date and time zone both correct in app and PC, they are.

Alas after going through the above I’m getting to my wits end so I’ve come on here in the hopes that someone may be able to help as its driving me nuts not being able to access a simple folder which has had access for years.

Oh and recent diagnostic report sent, ref number - 1403024293 (for any Sonos reps on here)

And just for ref the controller is installed on a Windows 10 PC, with an external NAS drive connected via Ethernet.