# Method not found: 'Microsoft.CodeAnalysis.SyntaxTree..........' error while invoking code

**URL:** <https://forum.uipath.com/t/method-not-found-microsoft-codeanalysis-syntaxtree-error-while-invoking-code/455255>\
**Category:** Activities\
**Tags:** question, studio, system, activities\
**Created:** [July 9, 2022, 7:18pm UTC](https://forum.uipath.com/t/method-not-found-microsoft-codeanalysis-syntaxtree-error-while-invoking-code/455255 "2022-07-09T19:18:25Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![Yoichi](https://sea2.discourse-cdn.com/uipath/user_avatar/forum.uipath.com/yoichi/32/523754_2.png) [@Yoichi](https://forum.uipath.com/u/Yoichi)\
**Post date:** [July 10, 2022, 12:01am UTC](https://forum.uipath.com/t/method-not-found-microsoft-codeanalysis-syntaxtree-error-while-invoking-code/455255/2 "2022-07-10T00:01:31Z")

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Hi,

Which version of Studio and UiPath.System.Activities package do you use?

InvokeCode activity in UiPath.System.Activities package 21.10 (or higher) doesn’t support Studio 21.4 or lower as the following document.

> **[Invoke Code](https://docs.uipath.com/activities/docs/invoke-code)**
>
> UiPath.Core.Activities.InvokeCode Synchronously invokes VB.NET or C# code, optionally passing it a list of input arguments. This activity can also return out arguments to the caller workflow. Properties Input Arguments - The parameters that can be...

So, If your environment is like the above, can you try upgrade your Studio to 21.10 etc OR downgrade System.Activities package to 20.10 etc.

Regards,

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