Missing or Invalid Activity in Workflow : This activity is either missing or could not be loaded properly

I have installed all the necessary packages required for the project

But still i am getting following error. how can it be solved

Please help me out here. I downloaded this file from our forum as one of the user has given me solution but my UI path is throwing this error

Hi @abhide,

This generally happens when you built a workflow using a specific versions of Project Dependencies & then upgrade the activities package (Most of the time it works) / downgrade the activities package (Generally Never Works). Please make sure you use the recommended versions of activity packages. Could you please share your UiPath Studio Version and the file you downloaded from forum, I can assist you further.


Hi @Nithin_P sir this is the attached screen shot

I am attaching the file too
project.json (919 Bytes)
Cumulate_numbers.xaml (25.4 KB)
Thanks in advance for help

Hi @abhide,

Looks like the workflow is built in the latest stable version of the UiPath Studio i.e. 2021.4.3.

The dependencies should be :

However since you have a lower version of Studio, you can try to upgrade the version of “UiPath.System.Activities” to 21.4.0. The workflow should load as expected.

If this doesn’t work install community version of UiPath on your personal laptop and check the workflow on that.

Hope that helps !

Thanks & Regards,

Thanks a lot @Nithin_P sir, I will look in to it. and let you know


i’m having the same problem accessing Activities. i have downloaded Uipath community version

Hi @Tonny_Tosh,

This generally happens when you are trying to open a file in lower version developed using higher version of studio or dependencies.

Can you show screenshot of the workflow and this file you have received from somewhere?