Orchestrator/Robot Tray Unable to start process(job) or install package


I am having issues with one of the robot users.

Everything was working fine yesterday and suddenly out of nowhere one robot user can’t start the process from the orchestrator or robot tray anymore.

We have 3 robot users profiles in the same machine (same environment)

The other 2 robots are still running as normal.

Every time i tried to start the process from orchestrator or robot tray i’m getting this following error messages =>

Cannot create unknown type ‘{http://schemas.uipath.com/workflow/activities}ShouldStop’.

RemoteException wrapping System.Xaml.XamlObjectWriterException: Cannot create unknown type ‘{http://schemas.uipath.com/workflow/activities}ShouldStop’.
at System.Xaml.XamlObjectWriter.WriteStartObject(XamlType xamlType)
at System.Xaml.XamlWriter.WriteNode(XamlReader reader)
at System.Xaml.XamlServices.Transform(XamlReader xamlReader, XamlWriter xamlWriter, Boolean closeWriter)

it’s actually a very long message I m just pasting a few.

I tried deleting the .nuget under the user profile. it didn’t work

I tried checking AppData Nuget. config with other robot user profiles (everything same)

Any advice on where to check next? I look around at all possible solutions in the forum and still can’t find the solution for it.

The only thing I can try is to create the new user profile to see if it will work or not (but I prefer not to do this as it will take me a lot of time to set up a user profile again).

I tried following step as well didn’t work =>

Thanks in Advanced


Hi @phyomt

I would strongly advise you to contact our technical support directly in case this is an Enterprise scenario:

These types of issues are typically related to the packages feed connectivity issues, but having it work on 2 users out of 3 with that one user profile failing makes it a bit strange.

Thanks @loginerror

I contacted technical support and they are looking into it. Unfortunately, couldn’t find the solution and I was advised to reinstall/update the studio and check the behavior. As the issues could be due to corrupted files somewhere or anything random.

That is likely, it could be one of the cache folders containing some corrupted files.

You could try deleting (or renaming) some of these folders for that particular user account:


These are user specific, based on the fact that only one user is causing the issue.