Sensor Upgrade Error: Incorrect parameters for Group Policy Object upgrade, GpoAllowUpgrade UPGRADE DENIED.

Products

• Carbon Black Cloud Endpoint Standard (formerly Cb Defense)
• Carbon Black Cloud Enterprise EDR (formerly Cb Threathunter)

Issue/Introduction

• Sensor upgrade fails with errors similar to:

  INFO       Incorrect parameters for Group Policy Object upgrade, GpoAllowUpgrade UPGRADE DENIED.
  ERROR     CAInstallPreCheck: DENY GPO upgrade.  Incorrect parameters for GPO upgrade.
  ERROR     Custom Action CAInstallPreCheck failed. : Incorrect parameters for GPO upgrade. Return code : 1603
  INFO      Ending custom action : CAInstallPreCheck. Return value : 1603.

• Previously using GPO to install/ update sensor

Environment

• Carbon Black Cloud Sensor: All Supported Versions

Cause

• Documented steps on Updating Sensors on Endpoints by using Group Policy were not followed
• The "CB Defense" registry key within HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\AppMgmt\ failed to be removed from the endpoint

Resolution

1. Confirm the documented steps for Updating Sensors on Endpoints by using Group Policy were correctly followed.
2. If the CB Defense registry key fails to remove itself after following the documented steps either:
   1. Manually delete it
      OR
   2. Script it's removal

Additional Information

It is not currently understood why the registry key fails to get removed at times. This may be an issue with environmental GPO variables or with older sensor versions.