Level 3 assignment 2 error - Invoke Process workflow: Value cannot be null, Parameter name : Expression

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1

Hi Devs.

Struggling with this one here.
I wasn’t even changing anything in the process.xaml file and had a successful run.
After it it stops upon reaching process.xaml invoke method.
It says :
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Arguments are passed and are not null.

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There isn’t even a variable or argument called “expression”.
I tried deleting and adding Invoke workflow again but it hasn’t helped.

Any ideas anyone?

2

@Aryx
What is TransactionItem in the calling workflow? Is it a String or a Queue Item or something else?

3

TransactionItem is a string type variable.

4

@Aryx

Please try adding breakpoints and run the process in debug mode and post a screenshot of where it breaks please.

5

It breaks when it reaches the Invoke processs.xaml,
That message was captured during debugging.

6

@Aryx

  1. Please check if the Invoked process Name , path etc are correct.
  2. The mapping between the arguments , the direction of the arguments, the type of the arguments.

If nothing works try doing the Invoke Workflow File part again.

7

Done all the above already, mentioned in the 1st post.
As I said the error makes no sense to me.

9

@Aryx I’m currently hitting the same issue. Would you happen to already have a resolution for this? Thanks!