Release : 14.X
Component : IdentityMinder(Identity Manager)
Navigate to Endpoints > Manage Endpoints > Modify Endpoint > Select Active Directory from the drop down and search.
Once you have found the appropriate endpoint definition click select.
On this screen you will be able to modify the user name and password for managing that endpoint.
You may also do this via Provisioning Manager by doing the following:
> Log in to provisioning manager
> Select Endpoints
> Select the Endpoint type
> Click Search
> Right click on your Endpoint and select properties
> Click on update under the server section, next to User ID
> Provide your new credentials
> Select OK