Troubleshooting: Access to XMLHttpRequest Blocked by CORS Policy

Version Affected: All
 
 

Overview

A browser blocks a request to a SecureAuth realm with an error similar to "Access to XMLHttpRequest has been blocked by CORS policy: Request header field <field> is not allowed by Access-Control-Allow-Headers" — for example, with tokenid as the blocked field.

 

Cause

The realm's configured HTTP Response Headers in IIS do not yet allow the specific header field named in the error.

 

Resolution

Confirm the field named in the error is one you want to allow, then:

1. Open IIS Manager and navigate to the realm.
2. Double-click HTTP Response Headers.
3. Add a custom response header named Access-Control-Allow-Headers, with the blocked field name (for example, tokenid) as its value.

SecureAuth Knowledge Base Articles provide information based on specific use cases and may not apply to all appliances or configurations. Be advised that these instructions could cause harm to the environment if not followed correctly or if they do not apply to the current use case.

Customers are responsible for their own due diligence prior to utilizing this information and agree that SecureAuth is not liable for any issues caused by misconfiguration directly or indirectly related to SecureAuth products.