Python Scope throws an error on the latest UiPath.Python.Activities 1.9.0 and NET8

Feedback Activities
,
1

Thanks!

One strange problem I’m getting - code that ran fine with the previous python alpha package 1.9.0-alpha.5252821 refuses to run with this updated package, always giving me: Python Scope: Error initializing Python engine

All arguments are the same and downgrading back to the alpha version reliably fixes it. I have tried explicitly installing both the .net 6 and 8 frameworks, any idea what might be going wrong?

2

Hi,

I am also running into the same problem

image
image1502×915 300 KB

I have dotnet 8.0.2 in C:\Program Files\dotnet

3

Hey @Matias_Tika @g.ward

Would you mind running this command in your CMD to double check and show us the output?
dotnet --list-runtimes

4

Hey,
Thanks for your response.

I have actually solved the issue. Looks like I didn’t have the SDK installed. I had “dotnet-hosting-8.0.6-win.exe” which is something else.
I installed the .NET 8 SDK and it works perfectly now.

Thanks again

1 Like
5

Hello @loginerror, do you have any idea what I could else check if I keep receiving exception ‘Python Scope: Error initializing Python engine’ with more details:

RemoteException wrapping System.InvalidOperationException: Error initializing Python engine  ---> RemoteException wrapping System.InvalidOperationException: Python deserialization exception  ---> RemoteException wrapping System.ArgumentNullException: Value cannot be null. (Parameter 's') 
   at System.ArgumentNullException.Throw(String paramName)
   at System.Text.Encoding.GetBytes(String s)
   at UiPath.Shared.Service.PythonResponse.Deserialize(String json)
	--- End of inner exception stack trace ---
   at UiPath.Shared.Service.PythonResponse.Deserialize(String json)
   at UiPath.Python.Service.PythonProxy.RequestAsync(PythonRequest request,
CancellationToken ct)
   at UiPath.Python.Service.PythonProxy.Initialize(String path,
String libraryPath,
Version version,
String workingFolder)
   at UiPath.Python.Impl.OutOfProcessEngine.Initialize(String workingFolder,
CancellationToken ct,
Double timeout)
   at UiPath.Python.Activities.PythonScope.ExecuteAsync(NativeActivityContext context,
CancellationToken cancellationToken)
	--- End of inner exception stack trace ---
   at UiPath.Shared.Activities.AsyncTaskNativeImplementation.BookmarkResumptionCallback(NativeActivityContext context,
Object value)
   at UiPath.Shared.Activities.AsyncTaskNativeActivity.BookmarkResumptionCallback(NativeActivityContext context,
Bookmark bookmark,
Object value)
   at System.Activities.Runtime.BookmarkWorkItem.Execute(ActivityExecutor executor,
BookmarkManager bookmarkManager)

I am using:
Studio 24.10.1
Python activities 1.9 // Python 3.11.5 - user installation
Python Scope configured following the sample.

DotNet:
Microsoft.AspNetCore.App 8.0.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 8.0.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 8.0.13 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

.NET SDKs installed: 8.0.406 [C:\Program Files\dotnet\sdk]

Any idea what else could I check? Thanks!

1 Like
6

Also still getting this, similarly with:

The image displays the properties of a Python Scope, showing the path, library path, and target platform for Python 3.12 on an x64 system. (Captioned by AI)
The image displays the properties of a Python Scope, showing the path, library path, and target platform for Python 3.12 on an x64 system. (Captioned by AI)1216×183 5.33 KB

dotnet --list-runtimes
Microsoft.AspNetCore.App 8.0.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 8.0.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 8.0.13 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

–list-sdks
8.0.406 [C:\Program Files\dotnet\sdk]

UiPath 24.10.8

eventviewer shows this at the time the initialise python engine error occurs:

This image shows a system error message for Event 1026, .NET Runtime, indicating that the UiPath.Python.Host.exe application was terminated due to an unhandled exception caused by an invalid handle in the System.IO namespace. (Captioned by AI)
This image shows a system error message for Event 1026, .NET Runtime, indicating that the UiPath.Python.Host.exe application was terminated due to an unhandled exception caused by an invalid handle in the System.IO namespace. (Captioned by AI)748×567 89.9 KB

and here’s a bit more on the actual error that UiPath shows:

The image displays an error message stating that the UiPath Executor encountered a Python deserialization exception due to a null value in the parameter 's'. (Captioned by AI)
The image displays an error message stating that the UiPath Executor encountered a Python deserialization exception due to a null value in the parameter 's'. (Captioned by AI)1079×299 88.1 KB

Edit: Can still confirm that the same code on this machine does not error on the previous alpha package that runs on .net6

8

Thank you for all the input.

I moved the messages to a separate thread to be able to better track this situation.