If you are using groups or SmartObjects to get your destination users you can just retry the WF that went into error after you have added the users to the data store. 

If it is business logic you will need to fix the workflow and redeploy.

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Hi SaintGobain,

If you are using a variable as a destination, it might help if you look into the Live Instance Management API (LIM) You stated that you fixed the process already, but you don't want to delete the current process instances.

Maybe you can use LIM to to migrate active, in-flight processes from the 'broken' version of the workflow definition to the 'fixed' version of the workflow definition.

See: https://help.nintex.com/en-US/k2five/devref/5.6/default.htm#Runtime/WF-Manage/LIM.html

There is also a community tool that you can look at, called the "Process Version Migration Utility".
https://community.nintex.com/t5/K2-Five-blackpearl/Process-Version-Migration-Utility-v3-0-6/ta-p/176994

Using this tool, you can migrate the 'broken' process instance, to the workflow version where you fixed the issue, and then perform a 'GoTo' to an earlier step in the workflow.

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