AAD Error Installation Error "The Registry Key SetupFiles was not found."

I keep getting "The Registry Key SetupFiles was not found." when I try installing Azure Active Directory Connect on a 2012 r2 server. Anyone have any ideas?

here is the error log:

at Microsoft.Online.Deployment.PowerShell.LocalPowerShell.Invoke()

at Microsoft.Online.Deployment.PowerShell.PowerShellHelper.InvokeCommand(IPowerShell powerShell, Command command)

at Microsoft.Online.Deployment.PowerShell.PowerShellHelper.GetRegistryValue(IPowerShell powerShell, String keyPath, String valueName, Object& data)

[08:06:19.349] [ 1] [ERROR] Caught an exception while creating the initial page set on the root page.

Exception Data (Raw): System.Exception: The Registry Key SetupFiles was not found.

at Microsoft.Online.Deployment.Types.Providers.EnvironmentProvider.GetSetupFilesPath()

at Microsoft.Online.Deployment.Types.SoftwareComponents.AzureADSyncEngineComponent.InitializeMinimumVersion()

at Microsoft.Online.Deployment.Types.SoftwareComponents.AzureADSyncEngineComponent.CheckInstallationState(IEnumerable`1 installedPackages)

at Microsoft.Online.Deployment.Framework.SoftwareComponents.DependentSoftwareProduct.CheckInstallationState()

at System.Collections.Generic.List`1.ForEach(Action`1 action)

at Microsoft.Online.Deployment.OneADWizard.Runtime.Stages.DetectInstalledComponents.Execute(String& message, GlobalContext globalWizardContext, Boolean& isPasswordSyncSupported)

at Microsoft.Online.Deployment.OneADWizard.UI.WizardPages.RootPageViewModel.GetInitialPagesCore()

at Microsoft.Online.Deployment.OneADWizard.UI.WizardPages.RootPageViewModel.GetInitialPages()