404 - File or directory not found

[Rajasekhar k]

Hello All,

Im about to use Standalone launch, Im done with authorization and when trying to "Exchanges the Authorization Code for an Access Token" im getting the error

404 - File or directory not found, please provide the solution.

[Luis Enrique]

Is HTTP/1.1 part of your URI? I don't see that in my version of Postman.

You probably need to remove that from your POST URI line.

Should look like this:  https://fhir.epic.com/interconnect-fhir-oauth/oauth2/token

[Rajasekhar k]

Ok, thank you for the response, the above said issue is resolved but currently im getting an error ""invalid_client" , please find the below screenshot

[Luis Enrique]

Usually means one of the below is not correct. Get a new auth code, maybe expired and double check the redirect_uri is the same as in the original request. Not 100% sure but I think your redirect_url will be automatically encoded by postman? Try adding it without the encoding.

https://fhir.epic.com/Documentation?docId=oauth2&section=Embedded-Oauth2-Launch_Access-Token-Request_No_Refresh-Tokens

• grant_type: For the EHR launch flow, this should contain the value "authorization_code".
• code: This parameter contains the authorization code sent from Epic's authorization server to your application as a querystring parameter on the redirect URI as described above.
• redirect_uri: This parameter must contain the same redirect URI that you provided in the initial access request. The value of this parameter needs to be URL encoded.
• client_id: This parameter must contain the application's client ID issued by Epic that you provided in the initial request.

[Rajasekhar k]

Thankyou so much for the response, I have removed "encoding for redirect_url" as suggested for postman and added scope in the step1 for standalone launch to fix the issue.