Error Uploading Files: 403 Forbibben

About a week ago I migrated my ClearOS 7.x Home firewall from a physical to a virtual server using Proxmox. Everything runs great, performance is also exceptional having given the VM 6Gb of Ram and 2 CPU cores.

COS 7 VM is running on a 128Gb (/dev/sda) disk with a 1Tb (/dev/sdb) disk dedicated for ownCloud storage. I've used the Storage Manager app to bind "/dev/sdb1/owncloud/data" to "/var/clearos/owncloud/data". The bulk 130Gb of my ownCloud local files have uploaded to the server (my user acct has unlimited ownCloud storage)

This was working perfectly until a couple of days ago. local file changes made are not being uploaded to the ownCloud server. <b> Server replied "403 Forbidden" to "PUT...</b> and a <b> Server replied "403 Forbidden" to "MOVE... </b> errors appearing in the local ownCloud client.

If I logon to the ownCloud server web interface and make any file changes there, these changes are being reflected on the local machines ownCloud dir. I'm also no longer able to manually upload files to the ownCloud Web Interface either.

I can roll back the VM to a previous version however don't want to have to reconfigure some of the server settings. the 2nd 1Tb disk is NOT in the Proxmox backup job. That's been omitted on purpose.

The central.ownCloud.org site forums have a few posts on this however I'd rather run this past the ClearOS forum.