Hello v4ramshi -
This error indicates that the profile you are using to connect to Centera does not have permission to read the clip.
The most likely cause of this is that the clip is assigned to a virtual pool, and you are using either an anonymous connection or a profile/PEA file for a different pool. What connect string are you using to establish a connection to the Centera?
If you have the CLIPID you are trying to read, issue a show location for that clip in Centera viewer. This will tell you which profile/pool you need to have read access to be able to read that clip.
let me know if I shall assist you remotely.
Best regards, Holger