Are you trying to clean up your Opportunity Records? Did you end up receiving this error message when attempting to merge two Opportunities?
We offer the ability to have multiple different Opportunity Types for your convenience. You can manage these types by navigating to Settings > Core Records > Jobs & Opportunities:
That Invalid Merge message we received when attempting to Merge two Opportunities, would be because of different Opportunity Types.
For Data Retention, Crelate will not allow the merging of two different opportunity types. We only allow merging of the same opportunity type to help retain as much information as possible. Each Opportunity Type can have different Settings enabled, therefore, we can not guarantee the correct info is being transferred and merged appropriately.