Failed to open the WMI namespace [root\AppV].Error (0x8004100e) - App-V 5.0
Option 1 - Reinstall the App-V Client in the machine to resolve the wmi namespace issue. Option 2 - If you want to avoid reinstalling the App-V client, then try to reinitialize the wmi namespace. This can be done by using the below commands and running it in an elevated CMD. mofcomp "C:\Program Files\Microsoft Application Virtualization\Client\AppvClientWmiProvider\Remove.Microsoft.Appv.AppvClientWmi.mof" mofcomp "C:\Program Files\Microsoft Application Virtualization\Client\AppvClientWmiProvider\Microsoft.Appv.AppvClientWmi.mof" Option 3 - Alternatively check in wmimgmt.msc and restore appv wmi namespace.The below link is pretty old but should work. Link - http://eskonr.com/2012/07/failed-to-open-wmi-namespace-virtualapp-log