A document library we have implemented on our SharePoint 2010 environment is behaving strangely. It has been created using a custom content type with several multi-lookup fields. When a file is uploaded, it presents a form where the custom properties can be set. If the same file is uploaded again, it presents a form with the existing properties pre-filled.
We have created another document library (on another site collection) based on a custom list definition, and it behaves a little differently. When a file is uploaded, it presents a form where the custom properties can be set, the same way as the previous library. But then the file in uploaded again, the previously selected properties are missing.
I would expect the behavior of the document library which is created using the custom list definition to be the default SharePoint behavior.
Would you be able to let me know why a document library with the custom content type would behave differently? Is this because of any features that have been activated on the site collection or due to the difference in implementation?
Thanks in advance for any feedback or suggestions.