Versions Compared


  • This line was added.
  • This line was removed.
  • Formatting was changed.

Title: Failure Handler feature guide - ARGOS Low-code Try Catch

Q.  Is there are a try catch feature in ARGOS Low-code? How do you use the Failure Handler feature?


Failure Handler in ARGOS Low-code is similar to Try-Catch in programming.


When the scenario fails for any unexpected reason(s), the Failure Handler feature allows you to run pre-set actions to such as re-try, change approach, report, ignore and proceed, etc. These actions run immediately after the failure so that the automation software continues to run.


2 steps to use Failure Handler


    1. Design various “Failure Handling” actions
    2. Assign the Failure Handlers to the Operation(s)


Designing the Failure Handler


The Failure Handler setting screen can be opened from the Settings menu at the top left corner of STU (the main menu section.)

Then the following pop-up window will open. You can start defining your failure handler by just clicking the [+] sign.

Safety feature to avoid accidental infinite loop – Important!


To avoid accidental infinite loops, the Failure Handler feature prohibits the automation scenario to go back to any steps or operations that have proceeded the failed operations.


How to assign your Failure Handler to Operations


When you right-click on any of Operations or select a group of Operations in the timeline, the pop-up window include a menu “Set Failure Handler” like below.

By clicking on this menu, you will see a list of Failure Handlers that you have already registered. Just by choosing one of the pre-set Failure Handlers, the Operation will now execute the Failure Handler as the indicator of [FH] show up like below.

Failure Handler activation scheme diagram


Need help?

Technical contact to

May you search all documents,

In the STU toolbox, most of the tools are Python plugins which already has the Return Code scheme to provide failure handler mechanism. For the Python plugins, when no Return Code has been assigned by the plugin designer, the Failure Handler mechanism kicks in. Also, when the Return Code options has been set as “AbortAsError” the Failure Handler mechanism will be called for action.


On the other side, as the C# operations do not have the Return Code scheme, all failures will activate the Failure Handler scheme except for the following cases.


Erroneous cases where your scenario fails but DOES NOT trigger "Failure Handler" settings



When undefined group name or variable name is used in the scenario. In this case, PAM continues with a character string "Undefined Variable" and yields no errors.

Excel Basics

When undefined variable has been used as input

When no MS Excel has been installed locally


When the selected (target) scenario does not exist (has been deleted)


When a negative value has been entered at the Index field of the target image


When "Ignore OCR Failure" options has been checked


None of the failure at this operation will start the Failure Handler

Shortcut Keys

None of the failure at this operation will start the Failure Handler


When failed to set Wiindows clipboard when the pasting option has been selected


None of the failure at this operation will start the Failure Handler



When "Failure Handler" works



-If clipping image is not set

-When setting the search area smaller than the clipping image

-When entering characters in the index value

-When entering a negative value in the index value (to be changed to stop)


-If the corresponding window cannot be found with the entered information



-If the element cannot be found with the entered information



-If a javascript error occurs


-When a character string other than a variable is input


-If clipping image is not set

-If text image is not set

-When setting the search area smaller than the clipping image

-When entering a negative value in the index value

-When entering characters in the index value

-If there is no recognized text


-If there is no value entered

Excel Basics

-When "Write" uses a variable whose value is not set


-If the browser directly executed by the user is running


-When an operation that does not exist is selected

-If no operation is selected


-When handling as AbortAsError in Function Error

-In case of failure within the function


-When handling as AbortAsError


-If no scenario is selected


-When entering text in the value

Excerpt Include