@Jake Could you perhaps assist here?

Were you able to find a solution? I think I'm facing the same problem.

Hello Jasmin,

I found an imperfect but working solution :

There is no user interface in Nintex to delete a delegation BUT there is a web service that is capable of doing it as documented here :

https://community.nintex.com/t5/Technical-Issues/Unable-to-Delete-Long-Term-Delegation/ta-p/86831

So I created a Site Workflow with :

One variable that must appear on the start form "ID_Delegation"

A single action : Call a web service : /_vti_bin/NintexWorkflow/Workflow.asmx

Method to be called : "DeleteLongTermDelegationRule"

That method require one input : id (int) -> I put my variable "ID_Delegation"

Then, go to http://SITE/_layouts/15/workflow.aspx?ShowAll=1

Start that site WF but you have to input the ID of the delegation to delete

HOW TO GET THE ID ?

2 methods :

1) You have access to MS SQL Server management Studio, connect to you server SQL,

Database : NintexWorkflowDB

Table : [Delegation]

request should look like that :

SELECT * FROM [NintexWorkflowDB].[dbo].[Delegation]

Check the column [DelegationID]

2) no sql, 100% Sharepoint/Nintex :

Go to :

http://SITE/_layouts/15/NintexWorkflow/UserPreferences.aspx?username=ACTIVEDIRECTORYDOMAIN%5USERLOGINNAME

Check the url of the links shown on the right :

http://SITE/_layouts/15/NintexWorkflow/DelegationEdit.aspx?delegationID=27

you cannot click the link but you have the ID to input in the delete workflow

Then, up to you to recreate a delegation with different users or dates.

http://SITE/_layouts/15/NintexWorkflow/DelegationAdd.aspx

Bonus information :

Site administrators can set up long term delegation for other users if the Global Setting “Site administrators long term delegation” is enabled.

http://CENTRALADMINISTRATION/_admin/NintexWorkflow/TaskSettings.aspx

I hope this will help you and others ...