Chris Ryland writes:
I've got a folder from which I (mistakenly) deleted the "title" property.
When I try to add it back (title / string / <string value>), I get a Zope error: "Bad request / invalid or duplicate property id".
This is probably a Zope-for-Dummies-style question, but I'm a little stumped. (A quick Google search turned up nothing, though perhaps I'm not looking correctly.) No, it is a bug/weakness in Zope (explained in another thread --> mailing list archives).
Probably your best option: make a new folder, copy all content from the old folder into the new folder, delete the old folder. When you are proficient with Python, there is an alternative: you can temporarily eliminate the duplicate id check in "PropertyManager.addProperty" and add the title property again. Dieter