---
title: NSError userInfo Dictionary Keys
framework: foundation
role: collectionGroup
role_heading: API Collection
path: foundation/nserror-userinfo-dictionary-keys
---

# NSError userInfo Dictionary Keys

Keys in the userInfo dictionary of an NSError object when certain NSURL methods return an error.

## Topics

### Constants

- [keysOfUnsetValuesKey](foundation/urlresourcekey/keysofunsetvalueskey.md)

## See Also

### Constants

- [NSURL Schemes](foundation/nsurl-schemes.md)