ADODB.Command error ‘800a0cc1’

I recently got this error message in an application at work:

ADODB.Command error '800a0cc1'
Item cannot be found in the collection corresponding to the requested name
or ordinal.  

The explanation you will often receive about this error is that you are trying to access a data item that does not exist – typically, they’ll say, it means your dataset is empty. However, I have found another cause for this error: Assigning a value to a Stored Procedure Parameter which does not exist.

Previous versions of ADO let this slide, but the version that ships with Windows 2003 does not.

Hope this helps somebody.