A problem occurred accessing the credentials required for this Web Part. The cause of this error is that the SharePoint stored ...

A problem occurred accessing the credentials required for this Web Part. 

The cause of this error is that the SharePoint stored credential named [{0}], which is required by the web console environment that this Web Part instance uses, was not found. Contact your SharePoint Administrator to create this credential or reconfigure the web console environment named [{1}] to point to a valid credential.

System error text: {2}