I came across the same error in Denodo scheduler when the username or password is incorrect in the VDP Data source. Make sure that you have entered the correct user and password in VDP Data sources.
To create a job using VDP Data source by Kerberos authentication ensure that you have enabled the ‘use Kerberos‘ option in VDP Data Sources because by default it will be disabled and also, ensure that Kerberos authentication is properly configured in the server configuration.
For more information, you can refer to the following sections [Kerberos Setting](https://community.denodo.com/docs/html/browse/7.0/scheduler/administration/administration/server_configuration/server_configuration_sections#kerberos-settings) and [VDP Data Sources](https://community.denodo.com/docs/html/browse/7.0/scheduler/administration/creating_and_scheduling_jobs/data_sources/vdp_data_sources) of the Scheduler Administration Guide.
Also, you can refer to the Knowledge Base article [Kerberos configuration and troubleshooting](https://community.denodo.com/kb/view/document/Kerberos%20configuration%20and%20troubleshooting?category=Security) for troubleshooting errors related to Kerberos.
Hope this helps!