Web services error User Not Authenticated

Products

• CA IT Asset Manager
• CA Software Asset Manager (CA SAM)
• ASSET PORTFOLIO MGMT- SERVER
• CA Service Management - Asset Portfolio Management
• CA Service Management - Service Desk Manager

Issue/Introduction

I am trying to connect to Web Services. I am getting an error:

Server Error in '/APIService' Application. 
User Not Authenticated 

Environment

Release:
Component: ARGIS

Resolution

Go to C:\Program Files (x86)\CA\ITAM\WCF Service\bin.
Right click on the file CA.Applications.Web.WCF.dll.
Go to Properties.
Click the Details tab and note the Product Version.

Go to C:\Program Files (x86)\CA\ITAM\WCF Service.
Edit the web.config file.
Search for the line:
<add name="ITAMServiceBehavior" type="CA.Applications.Web.WCF.Behaviour.ITAMBehaviorElement, CA.Applications.Web.WCF, Version=17.0.0.114, Culture=neutral, PublicKeyToken=null"/>

Change the version to match the file properties.
Save the web.config file and retest.