"Failed to execute Check for NSX Application Platform version for upgrade" during NSX Upgrade pre-checks

Products

• VMware vDefend Firewall
• VMware vDefend Firewall with Advanced Threat Prevention
• VMware NSX

Issue/Introduction

• NSX Manager upgrade is blocked due to failed upgrade pre-checks: Failed to execute Check for NSX Application Platform version for upgrade. 

Error details: [UC] Error in REST call. URL = /napp/api/v1/platform/monitor/platform/status, Method = GET, Response = , Error = NOT_FOUND.

• NAPP(NSX Application Platform) has already been removed from the environment

Environment

VMware NSX

Cause

Even though NAPP has already been removed from the environment, the uninstallation has not completed cleanly. Some NAPP references still remain present in the NSX Manager database.

Resolution

The remediation steps require NSX Manager database clean up.
Please open a support case to have this done under guidance of technical support.