I am getting "Message: The request failed. The remote server returned an error: (501) Not Implemented."

Last updated: 2026-10-01

SharePoint Essentials Toolkit shows error message: The request failed. The remote server returned an error: (501) Not Implemented.

Error Message

When running a job using the SharePoint Essentials Toolkit you receive "Message: The request failed. The remote server returned an error: (501) Not Implemented."

Details

If you receive error messages connecting to the SharePoint site from the tool but are able to browse the site in your web browser, please verify the 'Authentication method' used in the tool. If that is correct, then please check the settings of your Network Load Balancer (NLB).

Fix / Workarounds

We have found several customers who reported this error and it was due to a mis-configuration of the NLB (Network Load Balancer) not forwarding/routing the web service traffic and connection correctly.

If you are still facing this issue after verifying the NLB is not the cause, please contact our support team.