# How do I trigger a task if at least one of a set of tasks fails?

Triggering an error notification email if one or more tasks fail from a set of multiple tasks is a common use case. Multiple incoming workflow links to a workflow task object by default operate with AND combination logic.  

In the following workflow, if all of the linked tasks, RunDataflow, RunDataflow1, and RunDataflow2, fail, the SendMail task will be triggered. 

<figure><img src="/files/j3V6bDzWhX0ICV5kAoGK" alt="" width="563"><figcaption></figcaption></figure>

If you want SendMail to be triggered if one or more tasks fail, you can use the OR object. With this flow, if one or more of the dataflows fail, the OR object will return a True, and the error notification email will be triggered.

<figure><img src="/files/jq0EDQtmq8Q3CoMhgInr" alt="" width="563"><figcaption></figcaption></figure>


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