You have problems with your Desktop Central Agent, installed on the managed computers, and you run the "Agent Diagnostic Tool". You get an Error "Desktop Central Agent is detected as an Image", during the process.
You have deployed an image of the Operating System along with the Desktop Central agent.
If you have deployed the image of the Operating Sytem with the Desktop Central agent along with it, then you will have to rename the computer and restart it for the changes to take effect. If you have not deployed an imaged OS, and you still have this problem, then it could be due to any changes in the hardware like Network Adopter, Mother board etc, . In such cases, you can follow the steps mentioned below:
In case you are not able to troubleshoot the error, and the problem still persists, then contact support team with the Desktop Central Agent Log files.