For those googling this error in the Update Management console in Azure:
System.Runtime.InteropServices.COMException (0x80240438): Exception from HRESULT: 0x80240438 at Microsoft.EnterpriseManagement.Mom.Modules.ChangeTracking.WUA.IUpdateSearcher2.EndSearch(ISearchJob searchJob) at Microsoft.EnterpriseManagement.Advisor.PatchManagement.WindowsUpdateHelper.GetUpdateSnapshot(TimeSpan timeout, Boolean onlineSearch, DateTime lastTimeUpdateApplied, IAutomaticUpdates2 automaticUpdates, UpdateModuleState state)
Fix: Exempt the server from group policies (or alternative solutions) that configure Windows Update. GPO’s override Azure Update Management and block the Azure agent from searching for updates.