Installing Preview into C:\Program Files (x86)\Microsoft Visual Studio\2019\Preview\Common7\IDE\devenv.exe
Using VS Instance c4bbe3f3 at "C:\Program Files (x86)\Microsoft Visual Studio\2019\Preview"
"C:\Users\danie\Downloads\VSIX - PreRelease\tools\vsixexpinstaller\VsixExpInstaller.exe" "C:\Users\danie\Downloads\VSIX - PreRelease\vsix\RoslynDeployment.vsix" /vsInstallDir:"C:\Program Files (x86)\Microsoft Visual Studio\2019\Preview"  /u
  Running as Admin.
  en-US
  Nothing to uninstall...
Using VS Instance c4bbe3f3 at "C:\Program Files (x86)\Microsoft Visual Studio\2019\Preview"
"C:\Users\danie\Downloads\VSIX - PreRelease\tools\vsixexpinstaller\VsixExpInstaller.exe" "C:\Users\danie\Downloads\VSIX - PreRelease\vsix\RoslynDeployment.vsix" /vsInstallDir:"C:\Program Files (x86)\Microsoft Visual Studio\2019\Preview"
  Running as Admin.
  en-US
  Installing local extension: 'C:\Users\danie\Downloads\VSIX - PreRelease\vsix\RoslynDeployment.vsix'

Unhandled Exception: Microsoft.VisualStudio.ExtensionManager.MissingPackagePartException: Exception of type 'Microsoft.VisualStudio.ExtensionManager.MissingPackagePartException' was thrown.
   at Microsoft.VisualStudio.ExtensionManager.InstallableExtensionImpl.InitializeNestedExtension(ZipPackage parentVSIX, IExtensionReference reference, Func`2 initialize)
   at Microsoft.VisualStudio.ExtensionManager.InstallableExtensionImpl.InitializeNestedExtensions()
   at Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.GetInstallableNestedExtensions(InstallableExtensionImpl parentExtension, IInstalledExtensionList modifiedInstalledExtensionsList)
   at Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.<>c__DisplayClass193_0.<PreviewInstalledExtensions>b__0(InstallableExtensionImpl ext)
   at Microsoft.VisualStudio.ExtensionManager.EngineExtensionMethods.<Walk>d__8`1.MoveNext()
   at System.Linq.Enumerable.WhereEnumerableIterator`1.MoveNext()
   at System.Linq.Lookup`2.Create[TSource](IEnumerable`1 source, Func`2 keySelector, Func`2 elementSelector, IEqualityComparer`1 comparer)
   at System.Linq.GroupedEnumerable`3.GetEnumerator()
   at System.Linq.Enumerable.<SelectManyIterator>d__17`2.MoveNext()
   at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
   at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
   at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
   at Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.PreviewInstalledExtensions(InstallableExtensionImpl extension, Boolean perMachine, List`1 previewedInstalledExtensions, IInstalledExtensionList modifiedInstalledExtensionsList)
   at Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.FindRecursiveInstallConflicts(InstallableExtensionImpl extension, IInstalledExtensionList modifiedInstalledExtensionsList, List`1 impactedExtensions, Boolean isNested)
   at Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.ExtensionRequiresAdditionalOperationForInstall(InstallableExtensionImpl extension, IInstalledExtensionList modifiedInstalledExtensionsList, Boolean isNestedExtension, InstallFlags flags, Boolean& performExtensionUpdate)
   at Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.InstallInternal(InstallableExtensionImpl extension, InstallFlags installFlags, IDictionary`2 extensionsInstalledSoFar, List`1 extensionsUninstalledSoFar, IInstalledExtensionList modifiedInstalledExtensionsList, AsyncOperation asyncOp, IProgress`1 progress, Version targetedVsVersion)
   at Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.BeginInstall(IInstallableExtension installableExtension, InstallFlags installFlags, AsyncOperation asyncOp, Version targetedVsVersion)
   at Microsoft.VisualStudio.ExtensionManager.ExtensionEngineImpl.Install(IInstallableExtension extension, InstallFlags installFlags, Version targetedVsVersion)
   at Microsoft.VisualStudio.ExtensionManager.ExtensionManagerService.Install(IInstallableExtension extension, Boolean perMachine)
   at VsixExpInstaller.Program.<>c__DisplayClass16_0.<Main>g__Install|7(IInstallableExtension installableExtension, <>c__DisplayClass16_4& , <>c__DisplayClass16_5& )
   at VsixExpInstaller.Program.<>c__DisplayClass16_0.<Main>g__RunProgram|1()
   at VsixExpInstaller.Program.Main(String[] args)