@Ark2024 

Hi

1. Regarding the permission problem:  You can also try reconfiguring the USB sharing settings to ensure all subfolders are properly shared and accessible.

2. For the disk space issue: This could be due to temporary files or other hidden files taking up space on the disk. You can try cleaning up temporary or unnecessary files on the disk to free up space. Additionally, reconnect the disk to the router or try connecting it to another device to see if the issue persists.

  @Joseph-TP Thank you but permissions are shared with everyone. I created a new folder which was accessible. THe moment I copy the media directories into it I cannot access the folder.

I access it via //192.168.1.1/ShareName

In terms of size I have more than 400 GB available. 

Is this a limitation due to the OS on the Router that prevents using the disk like a standard Windows Network Share?

Just on further testing I am discovering that the folder had an MKV file of 3.7 GB. I took that off and I can now access the folder. I placed another MKV file around 3 GB and same issue again. 

So is it a size thing? Other MKV up to 2 GB are in other folders and no issues. 

The error I get is

"FOLDER" is not accessible. You might not have permission to use this network resource. Contact the administrator of this server to find out if you have access permissions. The specified server cannot perform the requested operation.