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mayurim3258
mayurim3258
July 23, 2025
Question

Appian RPA Robot ArrayIndexOutOfBoundException while opening a robot

  • July 23, 2025
  • 4 replies
  • 0 views

I have created a new robot in Operations Console and the robot is "Online". When I am trying to open this robot, it is throwing error as "ArrayIndexOutOfBoundException". And the Robotic task also cannot execute and says "Robot_Not_Allowed". Why this is happening?

4 replies

shubhama926776
shubhama926776
July 23, 2025

It’s usually because your robot isn’t properly assigned to a Robot Pool, or the permission tags don’t match between the robot and the robotic task.
To resolve this, add your robot to a Robot Pool, assign that pool to your Robotic Task, and make sure the permission tags are the same on both the robot and the task.

Robot Pools
Create a Robot Pool
Build in Appian RPA

mayurim3258
mayurim3258Author
July 23, 2025

Hi, I have given same set of permissions to Robot, Robot Pool & Robotic Task. Still the issue persists.

shubhama926776
shubhama926776
July 23, 2025

If you've already matched the permission tags on the Robot, Robot Pool, and Robotic Task, the issue may be due to the robot not being explicitly added to the Robot Pool, or the Robotic Task not linked properly to that pool.
Also, ensure the service account running the robot has the required permissions and is part of the correct user group. Matching tags alone aren’t enough - the robot must be assigned to the pool, and the task must target that pool.
Try removing and re-adding the robot to the pool, and reassociating the task. 

harshas2775
harshas2775
July 24, 2025

In the Appian 23.4 release, there was a change in how robot security is handled. Before this release, robots were secured using permission tags. However, starting from the Appian 23.4 release, newly created robots can only be secured using role maps.

If you are working on Appian 23.4 or higher, check & ensure that you have 'Editor' or 'Administrator' permission level for the Robot

If after verifying the security of Robot, Robot Pool and Robotic Task the issue still persists then try to restart the Robot from Operations Console and see if it works! 

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