Call Web Service action returns '401 Unauthorized' error with valid credentials

ISSUE

 

When using the Call Web Service action in a SharePoint On-Premises environment, the action fails regardless of what credentials are used.
 

ERROR CODE

 
The Remote Server Returned An Error: (401) Unauthorized
 

RESOLUTION

 

  1. Attempt to access the web service end point via the browser on all Web Front End servers.
  2. Locate the server where the web service end point fails.
  3. Execute one of the following steps to disable loopback check on the Web Front End server:
    • Via an administrator SharePoint Management Shell window run: New-ItemProperty HKLM:\System\CurrentControlSet\Control\Lsa -Name "DisableLoopbackCheck" -value "1" -PropertyType dword
    • Manually disable loopback checking in the registry:
      1. navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
      2. Create a DWORD32 entry for DisableLoopbackCheck
      3. Set the value to 1
 
Version history
Revision #:
4 of 4
Last update:
‎11-18-2020 08:43 AM
Updated by:
 
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