Error: 'install download or verification of installer failed' when Managed Antivirus - Installation Fails

Last Modified

Thu Oct 05 19:20 GMT 2017


  • Managed Antivirus installation failed
  • Summary tab shows Managed Antivirus - Installation Failed
  • Error in C:\Program Files (x86 if 64bit)\Advanced Monitoring Agent (GP if Group Policy)\debugfeature.log:
    • 09-09-2015 20:43:14: winagent(3904): BreckAgentInstallSettings::load<MavBreckCredentials><AgentID>144776</AgentID><AgentKey>f1af0961-726c-4e16-8ec7-d867f234914d</AgentKey><EncryptKey>6adf1b5e-9f12-498e-ba5c-cc6294e69f04</EncryptKey><InstanceHost></InstanceHost><InstallerDownloadUrl></InstallerDownloadUrl></MavBreckCredentials>
      09-09-2015 20:43:14: winagent(3904): BreckAgentInstallManager::downloadInstaller getting installer
      09-09-2015 20:48:21: winagent(3904): CMavBreck::_install download or verification of installer failed, see debug.log
      09-09-2015 20:48:21: winagent(3904): CFeature::install ManagedAvBreckenridge installation failed


  • N-sight RMM
  • Managed Antivirus (Bitdefender)


  1. On local device launch Advanced Monitoring Agent from Start Menu
  2. Enter password
  3. Select Edit Agent Options... > Connection Settings tab
  4. Ensure all Proxy values are blank
    • Please note: If proxy values are not blank and device is not using proxy please delete all proxy values
  5. Open services.msc
  6. Stop Advanced Monitoring Agent service
  7. Navigate to C:\Program Files (x86 if 64bit)\Advanced Monitoring Agent (GP if Group Policy)\downloads
  8. Delete ManagedAntivirusInstall.exe
  9. Open Notepad as Administrator
  10. Browse to C:\Program Files (x86 if 64bit)\Advanced Monitoring Agent (GP if Group Policy)\settings.ini
  12. Change INSTALL_ERROR_COUNT=3 to equal 0
  13. Save file
  14. Start Advanced Monitoring Agent service