Exam 1Y0-402 topic 1 question 18 discussion

Scenario: While assessing the User Layer, a Citrix Architect finds that most of the internal users connect using corporate-owned laptops, desktop devices, and thin clients. Many of these laptops and desktop devices are running Windows 10, while the remainder of the machines are running Windows 7 and are in the process of being migrated to Windows 10. Some users also connect using personal devices which have Receiver Desktop Lock installed.
Currently, Citrix Receiver is manually installed on any endpoint device added to the company. All these devices use Citrix Receiver version 4.8 and above. The IT team is planning to automate a process to update all the devices with the latest version of Citrix Receiver and to automate another process for automatic installation of Citrix Receiver without incurring extra costs and maintenance.
During the initial testing of the Citrix Receiver Auto-Update feature, the architect observed that the Citrix Receiver Auto-Update feature does NOT work on some of the machines.
Which two reasons could be causing this issue? (Choose two.)