ISSUE:
Missing pipelines from Data Collector after registering it with Control Hub.
RESOLUTION:
If a user can verify that the pipelines are still present in the DATA directory and nothing changed on the Data Collector side, the new Control Hub user probably does not have permissions to preview pipelines in the registered Data Collector. The user should verify if he/she has "Engine Administrator" role assigned in Control Hub --> Administration --> Users. This role can perform all tasks in registered Data Collectors and Transformers.