What is this error?

Occasionally, when I am writing Uipath programs, I see this error.

The error exclamation mark appears in the outermost sequence, and when I move the cursor over it, I get a very long list of error message.
Normally, when an outer layer has an error mark like this, it says “One or more children have validation errors” but this weird error is not that case.

What’s even more weird is, when I look inside this sequence, I don’t see any error icon anywhere.
To make matters even worse?, if I click on Analyze File → Validate File from the top pane of UiPath Studio, it says there is no validation error, and this error mark also goes away.

Sometimes, when I reopen the xaml file in question, the error mark has been back on!
Can anyone explain this to me, and is there anything I have to do? Does this mean something is wrong with the code?

Hi @tomato25

Null value is coming. At some point of your execution null values are getting assigned dynamically :slight_smile:


Does that mean, null values are getting assigned from outside? or within?

Like passing a null argument using Invoke activity?

Hi @tomato25

usually Null reference means it is expecting a value but the value is null, as per your screen I also see that you are getting the blue error which you are missing the passing values

Your screen is not clear as you hide all the information, if you say what you are trying to do and where you are getting error, then sure we can try to help you


Hi @tomato25

You can go to debug mode and investigate. this will show from values are getting null.

Roshan :slight_smile:

But why doesn’t it tell me where exactly the null value is happening?
This blue error mark is appearing on the outer most sequence layer, but any child sequence or activity does not have this error mark.


Blue error mark indicating that the sequence is having some missing values, if you not able to found, checke the properties of each activities, hope some variable is giving you the error