Update README.md

serverside/jsmod/README.md

@@ -11,3 +11,7 @@ The files that are modified are..
 * `/usr/share/pve-manager/js/pvemanager.js`
 * `/usr/share/javascript/extjs/charts.js`
 * `/usr/share/javascript/proxmox-widget-toolkit/proxmoxlib.js`
+
+### Backup unavailable
+If the backup you have is unavailable/not working, then you can either get the original file from this repo directory (if you have one of those 3 supported versions) or you can update your PVE install to the latest version by following this - https://pve.proxmox.com/wiki/Downloads#Update_a_running_Proxmox_Virtual_Environment_6.x_to_latest_6.2. 
+Updating will replace the files (apart from charts.js - whose original you can grab from any PVE version folder from here since its not changed).