Agent Client Collector Windows Upgrade or Installation Failure<!-- /*NS Branding Styles*/ --> .ns-kb-css-body-editor-container { p { font-size: 12pt; font-family: Lato; color: #000000; } span { font-size: 12pt; font-family: Lato; color: #000000; } h2 { font-size: 24pt; font-family: Lato; color: black; } h3 { font-size: 18pt; font-family: Lato; color: black; } h4 { font-size: 14pt; font-family: Lato; color: black; } a { font-size: 12pt; font-family: Lato; color: #00718F; } a:hover { font-size: 12pt; color: #024F69; } a:target { font-size: 12pt; color: #032D42; } a:visited { font-size: 12pt; color: #00718f; } ul { font-size: 12pt; font-family: Lato; } li { font-size: 12pt; font-family: Lato; } img { display: ; max-width: ; width: ; height: ; } } Symptoms On a Windows device, upgrading the Agent Client Collector via the Instance fails. Upgrading the Agent Client Collector via command line fails. After uninstalling Agent Client Collector, a new installation of Agent Client Collector fails. Example Scenarios We have seen in one case where the agent upgrade failed for some reason, then the agent was manually uninstalled, and a new installation of ACC fails, even though the ACC service no longer exists, the files in ProgramData and Program Files no longer exist, and ACC does not show up in the "Add or Remove Programs" page. We have also seen a case where the agent successfully upgrades from one version to another, but then fails a subsequent upgrade. Root Cause We have seen that for these devices that cannot install ACC again or cannot upgrade ACC, one or more older versions of ACC exist in the device's database of installed software. In the upgrade scenario, where the agent was previously successfully upgraded but is now failing to upgrade to the newest version, only the current version of ACC should exist in the device's database of installed software. In the scenario where ACC was uninstalled and the new installation is failing, no version of ACC should exist in the device's database of installed software. We believe that the presence of these old versions is causing the upgrade or installation to fail. We have seen in all the cases where we found old versions of ACC on the machines, SCCM was used to deploy the agent. Agent deployment through SCCM, where SCCM is trying to install an older version of ACC than what is currently installed on the device is creating these registry entries for the old version of ACC. Test Here is a test script that can be run on the Windows device that will show if the device has old versions of ACC registered. PowerShell command, run from PowerShell get-wmiobject -class Win32_product Sample Output: ... IdentifyingNumber : {4F3DB09D-5E1D-4EA8-B42A-C0F1C6365F92} Name : Agent Client Collector Vendor : ServiceNow, Inc. Version : 5.0.0.2 Caption : Agent Client Collector IdentifyingNumber : {617D389D-AD52-43DA-8A21-F297A5D90322} Name : CrowdStrike Firmware Analysis Vendor : CrowdStrike, Inc. Version : 7.14.18456.0 Caption : CrowdStrike Firmware Analysis ... This queries the installed software database and lists out the products that are in it, with their version. If the agent is installed, you should only see one entry for "Agent Client Collector" in the output. If the agent is not installed, you should not see any entry for "Agent Client Collector". The command output includes the version information, which is helpful to know which old version is being detected. Registry Query command, run from command line reg query HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products /s /f "Agent Client Collector" Sample Output: HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products\D90BD3F4D1E58AE44BA20C1F6C63F529 ProductName REG_SZ Agent Client Collector End of search: 1 match(es) found. This command performs a registry query, searching the "HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products" registry location for any occurrences of "Agent Client Collector" in its subkeys and their values. If the agent is installed, you should only see one match for "Agent Client Collector" in the output. If the agent is not installed, you should not see any matches for "Agent Client Collector". This output does not include the version information so it is harder to understand which version each match represents. Understanding the Results If you do see multiple entries for ACC when the agent is installed, OR if you do see one entry for ACC when the agent is not installed, manual intervention is required to clean up the extraneous version(s). Remediation The attached "AgentClientCollectorCleanup.ps.zip" contains a PowerShell script called "AgentClientCollectorCleanup.ps1". This script does a complete uninstallation of ACC. It does a thorough clean up of all ACC-related registry entries, files, services, and users. WARNING: This script does not back up any ACC configuration. Please be sure to backup any configuration as needed before running the script. After running the script, ACC will need to be installed fresh on the device.