Symptoms

User receives following error whenever trying to access any Appit-driven pages within SP environment:

An error occurred trying to process the request.

K2TSTS10002: An error occurred while processing a WS-Federation sign-in response

AADSTS16000: Session is invalid due to recent password change. Trace ID: ___ Correlation ID: ___ Timestamp: ___

Updates to K2Trust caused the security token associated to AAD authentication to become out of sync.
 

Diagnoses

First noticed when attempting to Appify a list/library. It appears to happen on any Appit application and in K2 Management.

An expired security token has persisted in cache of the browser.
 

Resolution

Clear cache in browser and log back in to SharePoint. Navigate to K2 Management. During navigation, K2Trust will reauthorize security token.