I received an email that was generated from a workflow that was created maybe around 6 months ago.
There is no clue in the email as to where the workflow was generated from. Our SharePoint site is very big.
I assume you are referring to a standard notification email from a task action, correct?
If it was it from some type of list workflow...
then the email typically contains a link containing the "Context Item URL". The context item URL will have the following format:
[ServerUrl]/[site]/Lists/[ListName]/DisplayForm.aspx?ID=[Item ID] -- or --
Based on this you can determine, exactly which site, list and item the workflow was related to. You can then view the workflow history for that item. If there was only one workflow for that item, then you're done. If there were multiple workflows on that item, further research might be needed.
If it was from a site workflow...
then there is no Context Item URL, so it could be a little trickier. The email would typically have a link to the related task, which would have the same format as the first URL above, so you would know which site, task list and specific task item the workflow was related to. The task may have details that describe where it came from, but it may not. But the task list will have a column called "Workflow Name" that you can enable in one of the task views to at least know which workflow it came from. This won't identify which workflow instance it came from, but you'll at least know which workflow process it came from.
if you dont know which workflow could be responsible, try the FindWorkflows operation from the NWAdmin tool. You can use this to list all workflows and their locations in the farm.
You can find documentation here:
SP 2010: NWAdmin Operations - Nintex Workflow 2010
SP 2013: NWAdmin Operations - Nintex Workflow 2013
Hope that helps!
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