DRAFT KB-XXXX "Unexpected token < in JSON at position 0" Error

Symptoms

Users who login using SAML occasionally see the following error when navigating around Appian:

This error appears in the following scenarios:

• Users are inactive in Appian for a prolonged period, and the session timeout in Appian and the IdP have different values.
• A user logs out of Appian in one tab while still having Appian open in a second tab. When navigating around the second tab, they see this error.

Other symptoms:

• Refreshing the page causes the error to disappear.
• A network capture's response content will show HTML for a webpage, usually the Appian or IdP login page.

Cause

The Appian session has timed out, and Appian is pulling the Login Page as HTML, rather then redirecting users to it.

Action

• Refreshing the page will resolve the error.
• There is currently a product enhancement to track this behavior in AN-87093.
• IdP timeout should be the same as Appian Timeout

Affected Versions

This article applies to all versions of Appian.

Last Reviewed: August 2019