I am trying to setup a workflow for a datasheet list that would send an email when a field in an item is changed to particular value and only once – not when you change any of the other fields. This would be like a status so when the field is changed to another value – nothing will happen and if the field is changed to that particular value again the workflow runs again. Is this possible?
Create an additional column in your list which can be excluded from the datasheet view. Make it a choice column called Email Flag with the default value being no.
In SharePoint Designer you create a new workflow that fires on item change. You create a condtion If Field equals XXX and Email Flag equals No and create an Action to email a user and Update an item. The update item sets the Email Flag to Yes and prevents the workflow from refiring.
Publish the workflow and emails will be sent to the specified user when the condition is met.
I have sorted out. Not that difficult in the end. https://blogs.msdn.microsoft.com/sharepointdesigner/2008/08/08/how-to-run-a-workflow-when-a-specific-field-changes/ this helped.