UserPassword grant type issue

[tdigby]

Hello,

I'm attempting to use the UserPassword method to authenticate with Salesforce and keep getting the following response from Salesforce:

`400 Bad Request` response: {"error":"unsupported_grant_type","error_description":"grant type not supported"}

I've tried connecting with and without the consumer key and secret credentials and that doesn't make a difference.

I assume something isn't set up correctly in Salesforce but I'm not sure what or where that would be.

Could you point me in the right direction?

[omniphx]

You do need the consumer key and secret. Did you try appending your security token to your password? Sometimes that is required if your IP is not whitelisted

[tdigby]

I did manage to connect eventually via the client_credentials grant type. Salesforce appears to recommend this over the password grant type, so we'll probably stick with that.

I haven't tried adding the security token to the password but I'll give that a go and let you know whether it resolves the issue, in case others experience the same problem in future.

I also read numerous suggestions from Salesforce documentation and Stack Overflow posts that there is an option in Salesforce somewhere to enable the username-password flow but I haven't been able to track that down in the version of Salesforce we're using.

[omniphx]

One thing I've found helpful is to checking the login history for the user you are trying to authenticate. This might give you a clue about why you are getting this error. It's been while since I've done Salesforce work but from what I remember unsupported_grant_type is a generic error.