ODM Cannot save a workflow campaign: Save failed.

ISSUE

Error while trying to save the changes on a workflow Campaign record: 'Save failed. Please 'Cancel' and try modifying workflow again'

SOLUTION

We use a thirdparty tool on the browser side for designing workflow campaigns. This issue occurs when there is data mismatch between this tool and the database. We have addressed most of the scenarios when this issue occurs and validations have been added to handle most cases. However, in the rare case that it does happen, the only work around is to create a brand new new Campaign manually (without "copying" from the existing campaign).