The given key was not present in the dictionary.
If you see this error message in WSS chances are you have an active reference to custom field type but have not installed the field type. The “/_layouts/mngfield.aspx” page will throw this error in the above scenario. Two possible resolutions:
- Visit Central Administration and deploy (or re-deploy) the WSP for the custom field type. For me this is usually http://www.codeplex.com/CustomFieldControls and the Parent Child Field types.
- Remove the Site Column (SPField) objects with object model code. Requires developer skills.
