Robot freezes execution without error

[i-nes]

Hi everyone,

Let me explain to you this odd problem that I encountered.
I have developed a robot using UiPath Studio 19.10.4 that interacts with an application that’s accessible through a Citrix Server.

My robot was doing fine last Monday, running all day long. But since yesterday, now the robot freezes during execution: the logs stop at a certain point without launching any error. This can go on like this forever, we have waited 30 minutes waiting for the robot to either continue its execution or to terminate with an error. Nothing happened, we stopped manually the robot. The logs don’t mention this manual stop by the way.

I should specify that there is no infinite loop in my robot, it processes several elements from a DataTable, and treats the first ones without any issue. I am 100% sure that this does not come from the robot and the code itself since there was no problem until yesterday.

I don’t replicate that on all machines from which I can launch this robot.

My question: where can it come from?

• An application error (probably not since on certain machines I don’t have this behaviour)
• An internal UiPath error (my lead)
• Something else?

Thanks a lot!!

[alin.ferenczi (Alin Daniel Ferenczi)]

A freeze might appear due to low resources available on the machine.

Other causes might appear from activities when using simulate / send windows messages or when using WaitForReady property set to complete.

[i-nes]

Hi, thanks for your reply.
I’m currently investigating on your first lead, to see if it could come from a configuration matter.
The activity on which it freezes is a Get Full Text, without any simulate/send Windows message option, and it doesn’t have an option for the WaitForReady property. I even set it after I encoutered the issue to None, and it doesn’t resolve my issue.
I’ll keep you updated, thanks.

[i-nes]

Hi again,

Seems like the problem was due to the fact that the machine (VM) was configured with 2 processors instead of the 4 that are recommended by UiPath.
When upgrading to 4 processors, I no longer encounter this issue.
Still don’t know why it was working in the first place and then started to freeze…

Either way, problem solved, thanks a lot!