This error indicates the installed commander version on the PC does not match the backend version running on the chassis itself.
Most commonly seen when an upgrade has not been completed and/or during skip version upgrade/downgrades.
To resolve ensure you have installed both the correct verson of commander on your PC (verify under 'Help' 'About') and that the product file has also been updated via 'Admin' 'Appliances' 'Software Upgrade'
*Note: 'OS' is not currently used, the product file is the tgz found in the local PC Commander install for each platform.
If the above does not resolve your issue you may need to telnet to the machine for a manual upgrade, please open an SR with support to walk you through this process as needed.