Unexpected error has occurred during the library compilation process: The assembly compilation returned the following errors: * Expression is a value and therefore cannot be the target of an assignment

@Mahendra_Talari11

Welcome to forums

This happens when you convert your flow from Windows-Legacy to Windows workflow?
Then there were some expressions which you need to make changes
And also, check in Imports any namespaces are getting error with red mark

Thanks,
Srini

I am getting same issue, as a newbie having hard time understanding this

yeah me too

we would need more details on the code statements. In general, the issue is about:

  • a value assignment needs to be done on a receivable left end

Eg. myString = “abc” ← Here the left side end can receive the value of ABC

Not working:
myString.ToUpper() = “abc” ← to upper is returning the upper case transformed string, but cannot receive a value

Unexpected error has occurred during the library compilation process:
The assembly compilation returned the following errors:

  • Value of type ‘DataTable’ cannot be converted to ‘WorkbookApplication’.
  • Value of type ‘DataTable’ cannot be converted to ‘WorkbookApplication’.
  • Value of type ‘WorkbookApplication’ cannot be converted to ‘DataTable’.

this is the error i am getting while running the .xaml and there is no red mark in Imports can you please say the solution.

Hi @lakshmiprasanna

Are you using Invoke Code in your workflow? If so share your code

Else please share the workflow if possible

Thanks,
Srini

this is the workflow

I am currently experiencing the same problem

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Hi @Mahendra_Talari11 I figured out what was the problem with mine. I had some assigns with .ToString and it was therefore giving error.

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After I removed the .ToString in these assigns it stopped giving error and is working fine now. Hope this helps you! Spent three hours on this so hopefully I could save you some time.

4 Likes

What f@# people, and what does it matter if he is a newbie it doesn’t make you a better person, on the contrary, you can help and you only make these types of comments.

1 Like

How did you find that there was an error?
Did it highlighted? because I have an issue and I can’t find where is the problem