Call Web Service Web Method GetUserInfo From UserGroup.asmx Gives Inconsistent Results

QUESTION

Why when using the Call Web Service action to run the web method 'GetUserInfo' from the UserGroup.asmx file, some user account return results, while others error?

ANSWER

Before using the GetUserInfo web method, you will want to first run the GetUserLoginFromEmail web method and pass in the following XML code (edit the email address): 

 

<Users><User Email="USERNAME@DOMAIN.COM" /></Users> 

 

You will get an output in XML format, and the desired result is listed under "User Login".  You can use this value to properly execute GetUserInfo.

ADDITIONAL INFORMATION

If you want further clarification, you can use the web method GetAllUserCollectionFromWeb to return the info for all users that have accessed this site collection. You will see the login name for each entry.  Some accounts will have the Claims Identifier prefix, while others won't.