Cannot install package 'UiPath.UIAutomation.Activities'

Japan Forum
1

Hello.
I am a user of Studio 2026.0.197-cloud.24027 - Community License.
When I try to install “UiPath.UIAutomation.Activities” from “Manage Packages”, I receive the error “System.Collections.Generic.KeyNotFoundException
The given key ‘0’ was not present in the dictionary,” and the installation fails. Changing to an older version does not improve the situation either. However, from what I can see in the logs, the download seems to be successful.
If anyone knows what I should do or has any suggestions, I would greatly appreciate your assistance.

2

Hello

The dependencies of the relevant activity package may be corrupted, so for the time being,

%USERPROFILE%\.nuget\packages

I suggest deleting (or temporarily moving) that folder and trying to reinstall the activity package.

3

Thank you for your response.
I tried the method you specified, but the situation has not changed.
Just for testing, I created a new project and installed only the “UiPath.UIAutomation.Activities” package, and no issues occurred.
The problem seems to be with a project file that was created quite some time ago, so there might be some inconsistencies in the dependencies.

4

In that case, it could be a version issue with the other activity packages. Please check if upgrading the versions of the other activity packages improves the situation or, if the issue occurs even without depending on the xaml file, sharing a project with a xaml file that has no activities might allow us to validate it on our end.

5

@atsuo.takagi

Can you try follow

Go to dependencies section, right click on error package and click on Repair and see it works.

If not works above., give a try below as well

  • delete the package click on save. And close the studio, assistant if opens.
  • reopen the project Open Project.json file look for any line in that json file as UiAutomation delete that entire line.
  • Then again reinstall the package.

Let me know if this works

Happy Automation

6

Hi @atsuo.takagi,

You can try these steps below:

  1. Close UiPath Studio completely.
  2. Navigate to “%userprofile%\AppData\Local\UiPath.cache”; back up if you want, then clear its contents.
  3. Reopen Studio and try installing “UiPath.UIAutomation.Activities” again.

If clearing the cache doesn’t resolve it, check couple of things:

  • Check disk space on the drive hosting your user profile; a full disk can cause partial/corrupted extraction that manifests the same way.
  • Try adding a fresh local NuGet feed pointing to a new empty folder temporarily.
    Open Studio → Manage Packages, Go to Settings, In the Source field, type the local folder path, eg: “C:\Temp\NuGetTestFeed”, then, Click Add, then Save.

If none of the above works, it could be an issue form the product, try raising a query directly with UiPath support.

Cheers!

7

Close Studio and delete the contents of:

  1. userprofile.nuget\packages\UiPath.uiautomation.activities
    and also
  2. remove the cache: localappdata\UiPath.cache
9

Thank you all for your advice.
I was able to resolve the issue.

I followed the steps below:

  1. Backup the folder containing the .xaml files.
  2. Completely delete the folder that contained the .xaml files (including .project, .local, etc.).
  3. Create an empty folder in the place of step 2.
  4. Copy only the .xaml files that were backed up in step 1 to step 3 (do not copy the project.json file, etc.).
  5. Open the .xaml files in UiPath Studio and add the package.

It seems there was some inconsistency between project.json and the .project or .local folders. Your advice was very helpful as well. Thank you!