I have an issue in my SharePoint farm.
I've found duplicated site columns on a specific site (I guess this is coming from a previous wrong backup-restore of the site). I've cheked also the site collection level and other sub-sites and it's working fine. It only affecting to this specific site (named "Generic Workfow v2").
The duplicated columns are inside the "Nintex Workflow" group (Associated Content Type)
This is generating an error when I try to associate a site column on a specific Content Type. I've found this on the ULS logs.
System.ArgumentException:No two choices should have the same ID
I've tried to delete these sites columns, but SharePoint doesn't allow me to do it.
Site columns which are included in content types cannot be deleted. Remove all references to this site column prior to deleting it
I've found references of these columns in the hidden list "NintexWorkfows". Columns are used as metadata in this list.
¿What can I do to change these wrong references to the new ones? ¿Can I for instance export all my WF in this site, deactivate the Nintex Feature, delete the "NintexWorkflows" list, then activate the feature again (is regenerating the "NintexWorkflow" list from the scratch?), import my original WF and try to delete the site columns then?
¿Can I simply delete the columns on the "NintexWorkflow" list and associate the correct site columns instead?
I'll appreciate any kind of help.