DRAFT KB-XXXX 403 errors on sites following upgrade

Symptoms

After an upgrade, users in certain groups are testing and seeing their test accounts are no longer able to access certain sites, even when these users can see the sites in the navigation menu.

Users get a 403 Access Denied error when accessing the site.

The application server log shows the following error:

Caused by: com.appiancorp.core.expr.exceptions.ExpressionRuntimeException$AppianExceptionProvider: Expression evaluation error [evaluation ID = XXXXXX] : 
The Site [name=“XXX”] does not exist, has been deleted, or you do not have sufficient privileges to access its data. (APNX-1-4198-000)

Cause

This issue has been reported to the Appian Product Team. The reference number for this issue is AN-140947.

Action

Select the affected site on Appian Designer.
Click Security.
Save changes, but do not make actual changes to the site security, other than re-saving original security permissions.

Affected Versions

This article applies to all versions of Appian after an upgrade.