Unable to install exenstions and updates for Visual Studio 2017 RC (15.0.26014.0)

Question

I recently installed Visual Studio 2017 RC (15.0.26014.0) and was trying to install extensions. However while installing any extension using Tools->Extensions and Updates menu fails. Following is installation log.

27-Dec-16 10:35:19 AM - Beginning to install extension to Microsoft Visual  Studio Enterprise 2017 RC...
27-Dec-16 10:35:19 AM - Install Error : System.IO.FileNotFoundException: Unable to find the specified file.
at Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.GetCurrentSetupInstance()
at  Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.PerformSetupEngineInstall(InstallableExtensionImpl extension, Boolean installPerMachine, Boolean isPackComponent, IDictionary`2 extensionsInstalledSoFar, List`1 extensionsUninstalledSoFar, IInstalledExtensionList modifiedInstalledExtensionsList, IProgress`1 progress, InstallFlags installFlags, AsyncOperation asyncOp, IInstalledExtension& newExtension)
Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.InstallInternal    (InstallableExtensionImpl extension, InstallFlags installFlags, IDictionary`2 extensionsInstalledSoFar, List`1 extensionsUninstalledSoFar,
IInstalledExtensionList modifiedInstalledExtensionsList, AsyncOperation asyncOp, IProgress`1 progress)
at Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.BeginInstall(IInstallableExtension installableExtension, InstallFlags installFlags, AsyncOperation asyncOp)
at Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.InstallWorker(IInstallableExtension extension, InstallFlags installFlags, AsyncOperation asyncOp)

I checked and found corresponding VSIX file is present in temp folder (C:\Users\xxxxx\AppData\Local\Temp)

Answer 1

I'm currently having the same problems. According to this post, repairing the installation might help.