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- Username
Salesforce username as used to sign into the Web UI - Password
Salesforce password as used to sign into the Web UI - Security Token
An additional token generated by Salesforce for use with API access. Changes to the password will change the security token.
See Resetting Your Security Token
It will be required unless your current IP address is listed under Trusted Networks. - Client Id
This is the client identifier that appears in the call options header. It is only required if working on a certified app that requires API access to professional and group edition orgs. - Environment
Typically either Production for a standard org or Sandbox for an environment where you usually login with test.salesforce.com
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