Robot execution never ended/Robot got stuck




The following problem happened to me once, yesterday.

The robot was Windows Task Scheduled to run at 7:30 in the morning. It ran well, and got the job done mostly, except for the last 2 activities (send email, log message). When I looked at the computer at about 10am, because I hadn’t got any email, the UiRobot.exe icon was still in the taskbar, and the robot was running in the UiRobot trey icon. Then I manually ended the execution, and only then the ‘execution ended’ line appeared in the log file.

I have the Main Flowchart in a Try Catch block, and a Send Email -activity in the Catch section. So whenever there is an error, there should be an email message sent. This time, there was not even any email sent.

How the robot got stuck like this? It didn’t even get an error. Is there anything that could prevent this from happening in the future?


Hi @bluerock,

I think you should write line every step in your workflow. So you can know exactly the step where robot get stuck at.

Best Regards,
Hoang Anh.


Hi Bluerock,

I can’t think of anything that would be causing the robot to get permanently stuck without any sort of error like this other than it getting caught in an eternal loop right before those last two activities. Do you have loops in your process? If so, you might try inserting one or more Write Line activities at key points in your loop(s). That way if you run into this issue again you should easily be able to tell if the robot has just been running in loops for the past several hours. I’ve used this method in the past to help me identify if a process is going through a loop more often than anticipated.

The only other thing I can think of that could cause an issue like this would be if you accidentally put an extremely long “TimeoutMS” value for a UI selector you’re trying to find in one of your last activities. If the TimeoutMS value is massive and the UI selector you chose wasn’t valid for some reason during your last robot run, it is possible the robot was just sitting there trying to find the UI selector that entire time.

Good luck!


Hi BB and Hoang Anh!

Neither was the case, unfortunately. I have log messages after almost every activity. And I haven’t edited any TimeoutMS values either…

Thank you for the answer anyway!


Very strange! Is it possible for you to remove the sensitive portions of your project and upload it here to the forum? Off the top of my head I can’t think of what else could be causing this, but I’ll take a look at the project and maybe something will come to me if you can upload it.

Also, you didn’t specifically mention this in either of your other posts, but I get the sense that this is a process you have run successfully before. Is that correct?



Sorry for delayed response! But yes, this is running successfully, and has run successfully now every day except for that one time.

Unofrtunately I cannot upload the project workflow here at the moment. It would take some time to anonymise the version. I do not think there is anything in the project, that would cause this.

Thanks anyway!