Error when opening PDF file by Acrobat Reader DC on StudioX 2020.10.4

Currently I just use Use Application/Browser activity to open PDF file by Acrobat Reader DC on StudioX 2020.10.4.
It can opened but show error message as below.
Could you help to suggest me, please? Please find the attached files for workflows file.
Something went wrong with the Application.
Activity Use Application: EquipmentAgreement.pdf - Adobe Acrobat Reader DC (32-bit) (N Application Card) failed:

Could not find the user-interface (UI) element for this action.

Possible solutions:
        •  Ensure application is opened and the UI element is visible on the screen at execution time
        •  Edit the Target of the UI activity and use Validation to debug the issue. 
        •  If needed, re-indicate the element as its properties might have changed
        •  Use "Check state" activity to check the application state before executing the action
        •  Increase the "Delay before" value to allow time to the application to render entirely and become responsive

You can find the activity following this path: 

Main > Use Application: EquipmentAgreement.pdf - Adobe Acrobat Reader DC (32-bit). (71.1 KB)

Hello @akkapolk!

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check this guide first. also, what version of UI Automation are you using, we ve fixed an issue with acrobat reader in our last release.