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Outbound fax failed with OAU-140
Tags: fax test
Dec 26, 2019 at 9:50pm   •   2 replies  •  0 likes

Hello, I have setup my first app with 'private' and 'server only(no UI)' and tried to test sending a fax under sandbox env. The first request went out and put into queue, however when I try to retest the same request, it gave me an error. Please advise. Thanks.

==Error info

WWW-Authenticate: Bearer realm="RingCentral REST API", error="invalid_grant", error_description="Invalid resource owner credentials"

RCRequestId: bb6be21c-286b-11ea-9d35-005056bbcdd9

Pragma: no-cache

Cache-Control: no-store

AceRoutingKey: sjc11-c01-ace11.8e816ecd-0d3b-11ea-9962-005056bb6e9b

RoutingKey: SJC12P01


"error" : "invalid_grant",

"errors" : [ {

"errorCode" : "OAU-140",

"message" : "Invalid resource owner credentials"

} ],

"error_description" : "Invalid resource owner credentials"


== my setting

static String RINGCENTRAL_CLIENTID = "app cient id";

static String RINGCENTRAL_CLIENTSECRET = "app secret";

static String RINGCENTRAL_USERNAME = "sanbox number";

static String RINGCENTRAL_PASSWORD = "sandbox password";

static String RINGCENTRAL_EXTENSION = "101"; //from sandbox

public static final String SERVER = "";

1 Answer
answered on May 9, 2020 at 1:24am  


answered on May 9, 2020 at 1:15am  


answered on Dec 27, 2019 at 9:00am  

There must be some mistake with your credentials somewhere. It is impossible if nothing changes and you could send once but not twice.

Please double check your code and follow the instructions from this dev guide and try again.


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