The ExpressionTranslationBuildTask task failed unexpectedly SharePoint Visual Studio Workflow Error
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This SharePoint workflow tutorial, we will discuss how to fix an error The ExpressionTranslationBuildTask task failed unexpectedly which comes while developing a workflow using visual studio 2015 for SharePoint online sites.
In one of our requirement, we have developed a workflow using visual studio 2015 for SharePoint Online. Here we were trying to send email using Email workflow activity.
In that activity, we have declared a variable and we were trying to assign it into the To field of the email. But it gave us error like:
The “ExpressionTranslationBuildTask” task failed unexpectedly….

The ExpressionTranslationBuildTask task failed unexpectedly
The solution to resolve the issue was to change the data type of the variable from String to Collection<T> type.
We have declared the variable like below:

To change the variable type, click on the variable type and then select Browse for Types… like below:

And then choose the System.Collections.ObjectModelCollection<T> type like below:

Now the error will not come.
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This tutorial helps to fix error The ExpressionTranslationBuildTask task failed unexpectedly which comes while developing visual studio workflow.

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