Permissions have changed, cannot save to FreeNAS directories

[Arelman]

Hi
I am a very basic newbie, running a FreeNAS box for about three years in a simple way.
A few months ago I discovered that I could not add new folders to my basic directories in FreeNAS. I have four directories in the root and was able to add/delete/rename directories under each of those root directories. (hope the terminology is correct).
Even though I could not add a new folder ie I wanted to add 2017-video to the Media directory but did not have permission, I could add a sub-folder to existing folders under Media.

In trying to fix this I have now been denied access to ALL the directories and folders. 'You do not have permission to access/change'.

I have since tried the Windows properties change permissions but I get error messages.
So I need help to work out how to get permission to access my own NAS.

OS Name Microsoft Windows 10 Home
Version 10.0.14393 Build 14393
Other OS Description Not Available
OS Manufacturer Microsoft Corporation
System Name ARELMEDIA_BOOT
System Manufacturer Gigabyte Technology Co., Ltd.
System Model G33M-S2L
System Type x64-based PC
System SKU
Processor Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz, 2400 Mhz, 4 Core(s), 4 Logical Processor(s)
BIOS Version/Date Award Software International, Inc. F2, 11/20/2007
SMBIOS Version 2.4
Embedded Controller Version 255.255

System Information
Hostname freenas.local Edit
Build FreeNAS-9.10.2-U3 (e1497f269)
Platform AMD Turion(tm) II Neo N54L Dual-Core Processor
Memory 8033MB
System Time Mon May 15 11:13:51 AEST 2017
Uptime 11:13AM up 1:57, 0 users
Load Average 0.40, 0.37, 0.37

I have four WD 3 Tb drives in the box.

If someone can assist I will be extremely grateful.

cheers

Roger

 

[Arelman]

in addition I have this screen re permissions:

 

[m0nkey_]

https://forums.freenas.org/index.php?resources/freenas-and-samba-smb-permissions-video.8/

 

[Arelman]

https://forums.freenas.org/index.php?resources/freenas-and-samba-smb-permissions-video.8/

Thnks for the link.
I have watched the video, rewound and replayed a few times, and attempted to implement the users/permissions.
I discovered I know even less than I need.
I had set up a user (media) and a group (media) that initially worked really well. Read and Write to every folder.
Now I am struggling to work out, because I don't have others logging in and requiring passwords and differing access levels, how the various users relate to when I turn on my computer - and I have always (until now) had direct access to the NAS.

Can I delete all my users and groups and reset all permissions that way?
Can I create another volume on the NAS, migrate data to it and recreate users/permissions?
Or do i just move it all from the NAS and start over?

(funny thing is - my Owncloud plugin, which has never turned on, is now ON!)