Failed to launch UI Explorer!

Installer(.exe or .msi): msi

License type(Free, Trial/License code): License code

Studio/Robot version: 2018.4.2

Current behavior: 2018.1.2



I got the following error message:

Installation Studio 2018.4.2 License code
Starting UIPath Studio → go to “Tools” and click at Apps on die button UI Explorer

→ Failed to launch UI Explorer!

Does anyone have a suggestion why it could be?
What happens when the button is pressed? Is an internet connection required?

Thanks for tips,



Hi @Just,
Seems that installation of studio can be somehow damaged. You could try to reinstall Studio based on this post:

Eventually please contact with our Technical Support.

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unfortunately did not work.

I deleted the directories before:


First, he needs a bit longer to show the error: Failed to launch UI Explorer!

But it’s the same result.

What happens behind the button?
Access to the internet?

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Which .Net version do you have?

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The last Version I see in the regedit ist v4.0.

But do i need a .net for the studio installation?

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The newest the better. Install the new 4.7.2 version and test if this solves the problem :slight_smile:

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Good idea. Unfortunately not so feasible, because it is a standard image for 5000 computers.

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But I guess this image is somehow provisioned through 5000 machines right? Like VMware golden image or Citrix PVS or Hyper-V image. There’s always a way to perform versioning or test version of image where you can do changes on image without impacting currently running computers from this image.

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There is a lot of technology possible, only the maintenance, test, rolling out a fat client image is not individually designed here.
I’ll try the next two Versions 2018.4.3 and 2018.4.4.
Let’s see what happens there.

PS: happy birthday

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Thank You :slight_smile:

So now on a different environment the installation has been done and UI Explorer can be started. .NET versions are identical. There seems to be a connectivity issue on the non-functioning environment.

Does anyone know what is called there exactly and may need to be unlocked?

I am having the same issue on 2021.4.0. popup says “Failed to launch UI Explorer!” when launching from tools menu.

However, when I have a project open in the design tab, I can open UI Explorer from the ribbon, then if I click Indicate Element I get a different popup, Screenshot 2021-04-14 151204

Try opening Explorer exe from the installation directory and see if it works.

Hi @david.brown,
Could you give us more details? Please also try to update the Studio to the newest preview version.

I followed @Pablito directions to reinstall after clearing nuget packages, and now I am able to launch ui explorer from tools menu and inspect ui elements

I am still getting errors trying to launch explorer from design window, while working on a sample project that I downloaded from ui academy. I am however able launch it from the tools menu. I guess the older project is calling for an unsupported version?

Could you upload this project so I could take a look at it?

Video Demo - Fine-tuning Selectors with Variables (workflow).zip (426.2 KB)

uploaded one of many, from the RPA Developer Foundation Lessons. Ironically I first noticed it in the Selectors course.

I tested it and seems that it’s working fine on my end. It is opening in the correct version as well.