Mobile number missing in Knox Manage Device Information tab

Environment

• Knox Manage

Overview

You may notice that the Mobile Station International Subscriber Directory Number (MSISDN, or mobile number) of a device’s SIM card doesn’t appear in the Device Information tab in Knox Manage. This is expected behavior caused by limitations in how SIM cards, mobile carriers, and Android systems work together — it isn’t an issue with Knox Manage.

How Knox Manage retrieves SIM information

Knox Manage retrieves SIM-related information directly from the Android operating system using standard system APIs. There are three key identifiers involved:

• IMSI (International Mobile Subscriber Identity) — Always available and displayed correctly.
• MSISDN (mobile number) — Optional and frequently unavailable.
• Carrier name — Depends on the network operator’s configuration and data exposure policies.

Why mobile numbers don’t always appear

Mobile numbers aren’t always stored on the SIM card. Even when they are, mobile operators may block access to this information for privacy or security reasons. Additionally, Android APIs don’t guarantee successful retrieval of MSISDN data, and carrier information may be incomplete or inconsistently exposed through system interfaces.

The key factors affecting data availability are:

• SIM card storage limitations and provisioning practices
• Mobile operator access restrictions and privacy policies
• Android system API constraints and data exposure inconsistencies

Cause

This behavior is caused by limitations at the SIM card and mobile operator level, not by Knox Manage.

In many enterprise deployments, the MSISDN field is left empty on the SIM card during provisioning. Mobile operators also frequently restrict access to mobile number data through their network policies, even when this information exists in their systems. Additionally, some devices can’t retrieve mobile number information due to compatibility issues between the SIM card, device hardware, and carrier network protocols.

As a result, Knox Manage can only display the information that Android makes available through standard system APIs, which often excludes mobile number data due to these external telecommunications limitations.