Open Application -Notepad.exe -class not registered exception

Hello experts,
i am a new learner. I installed the UI PathStudio and want to run lesson2 with open notepad.exe. Localy i can open notepad and put it into flowchart and open application. If i press the run button, an error message appear:


Source: Open Application ‘notepad.exe Unbenannt’

Message: Retrieving the COM class factory for component with CLSID {152E94B7-A0CA-45D1-BB2D-45656131A972} failed due to the following error: 80040154 Klasse nicht registriert (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG)).

Exception Type: System.Runtime.InteropServices.COMException

An ExceptionDetail, likely created by IncludeExceptionDetailInFaults=true, whose value is:
System.Runtime.InteropServices.COMException: Retrieving the COM class factory for component with CLSID {152E94B7-A0CA-45D1-BB2D-45656131A972} failed due to the following error: 80040154 Klasse nicht registriert (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG)).
at UiPath.Core.Activities.ScopeActivity.EndExecute(NativeActivityContext context, IAsyncResult result)
at UiPath.Core.Activities.AsyncNativeActivity.BookmarkResumptionCallback(NativeActivityContext context, Bookmark bookmark, Object value)
at System.Activities.Runtime.BookmarkCallbackWrapper.Invoke(NativeActivityContext context, Bookmark bookmark, Object value)
at System.Activities.Runtime.BookmarkWorkItem.Execute(ActivityExecutor executor, BookmarkManager bookmarkManager)

Can anyone help me? I use windows 7 sp1 (32bit)
Best regards Andreas

@andiy - Since you are running the latest version of UiPath Studio on Windows 7 (32 bit), please check if you can uninstall UiPath Studio and then re-install it by marking the UiPathStudioSetup-2019.1.0.exe as compatible with Windows 7. (Please see the screenshot below).

Also there are few users who reported this error earlier. Just search for “80040154 Class not registered” in this forum and you will see that some people solved this by uninstalling and reinstalling the UiPathStudio.

Hope this helps!

And Welcome to you from all of us UiPathers!

Hi Sreenivasm,
thanks for your quick reply. I did as you sugessted. Additionaly deleted all entries from registry that sounds like uiPath.
But at the end the rerror is still there.
When i installed the UIPathStudio again, i saw a interesting error in the log file:

12:25:44.7338 => [WARN] [UiPath.Studio.exe] [1] XamlMigration: removed reference UiPath.Core
12:25:44.7338 => [WARN] [UiPath.Studio.exe] [1] XamlMigration: removed reference UiPath.Core.Activities
12:25:44.7338 => [WARN] [UiPath.Studio.exe] [1] XamlMigration: added reference UiPath.UiAutomation.Activities
12:25:44.7338 => [WARN] [UiPath.Studio.exe] [1] XamlMigration: added reference UiPath.System.Activities
12:26:08.6102 => [ERROR] [UiPath.Studio.exe] [31] $LoadAssembly: UiPath.Vision, Version=, Culture=neutral, PublicKeyToken=null: System.IO.FileNotFoundException: Die Datei oder Assembly “Emgu.CV.World, Version=, Culture=neutral, PublicKeyToken=null” oder eine Abhängigkeit davon wurde nicht gefunden. Das System kann die angegebene Datei nicht finden.
File name: ‘Emgu.CV.World, Version=, Culture=neutral, PublicKeyToken=null’
at System.Signature.GetSignature(Void* pCorSig, Int32 cCorSig, RuntimeFieldHandleInternal fieldHandle, IRuntimeMethodInfo methodHandle, RuntimeType declaringType)
at System.Reflection.RuntimePropertyInfo.get_Signature()
at System.Reflection.RuntimePropertyInfo.get_PropertyType()
at ActiproSoftware.Text.Languages.DotNet.Reflection.Implementation.BinaryAssemblyLoader.#aFc(#Lrc #wAf, MemberInfo #xAf)
at ActiproSoftware.Text.Languages.DotNet.Reflection.Implementation.BinaryAssemblyLoader.#cFc(#hsc #4Ub, Type #uAf)
at ActiproSoftware.Text.Languages.DotNet.Reflection.Implementation.BinaryAssemblyLoader.#XEc(Assembly #sxc)
at ActiproSoftware.Text.Languages.DotNet.Reflection.Implementation.BinaryAssemblyLoader.#iFc(Assembly #sxc)
at ActiproSoftware.Text.Languages.DotNet.Reflection.Implementation.AssemblyRepositoryBase.#30j(Assembly #sxc, IAssemblyName #4tc, IBinaryAssemblyMetadata #RDb)
at ActiproSoftware.Text.Languages.DotNet.Reflection.Implementation.AssemblyRepositoryBase.Create(Assembly assembly, IAssemblyName assemblyName, IBinaryAssemblyMetadata metadata)
at ActiproSoftware.Text.Languages.DotNet.Reflection.Implementation.FileBasedAssemblyRepository.Create(Assembly assembly, IAssemblyName assemblyName, IBinaryAssemblyMetadata metadata)
at ActiproSoftware.Text.Languages.DotNet.Reflection.Implementation.FileBasedAssemblyRepository.GetOrCreate(Assembly assembly, IAssemblyName assemblyName, String location)
at ActiproSoftware.Text.Languages.DotNet.Reflection.Implementation.AssemblyRepositoryBase.#uBh(Assembly #sxc, IAssemblyName #4tc, String #bVe)
at ActiproSoftware.Text.Languages.DotNet.Reflection.Implementation.AssemblyRepositoryBase.Load(Assembly assembly, IAssemblyName assemblyName)
at ActiproSoftware.Text.Languages.DotNet.Reflection.Implementation.AssemblyRepositoryBase.Load(String fullName)
at UiPath.Studio.Plugin.Workflow.ExpressionEditor.SyntaxService.LoadAssembly(LoadIntellisenseAssembliesContext context, String assemblyName, CancellationToken cancellationToken)

But the file ‘Emgu.CV.World, Version=, Culture=neutral, PublicKeyToken=null’ is there. It is located in C:\Users\myuser.nuget\packages\\1.2.0\build\Emgu.CV.World.dll
The folder .nuget was created while creating the first project in Studio.

I think both messages caused by the same reason. Is there a problem with installation files?
I saw an similar error message with the file ‘Emgu.CV.World’ prompted to the forum some minutes ago
Best regards

@andiy - You can try closing the UiPath Studio, delete the .nuget folder and open UiPath Studio.

Hi sreenivasm,
only closing the UI Path Studio and deleting the .nuget folder could not resolve the Problem.
But the combination of deleting the .nuget folder and deinstallation the complete UI Path Studio, cleaning the registry, rebooting the system and installing UI Path Studio again ( as you described in compartibility mode “windows7” ( and “Change settings for all users”) led to resolve the problem.
Thank you very much for your help and
best regards

Awesome! :+1: