Symptoms

Error on K2 Smartform Viewer Sharepoint Webpart

Multiple authentication attempts detected
More details
Detected an instance where Relying Trust is not configured properly, and requesting tokens repeatedly. Please ensure that the link to the K2 Server is added to the browser's trusted sites
 

Diagnoses

Only a particular user experiences this and he is using Safari on a MacBook Pro to access this. They had cleared out the KeyChain but the error continues to appear several times a day.
 

Resolution

"Modify" rights were granted to the IIS_IUSRS group on the WindowsTemp directory