Why do I get 800A0C93 errors?

If you are getting one of these errors: 
 

ADODB.Recordset error '800a0c93'  Operation is not allowed in this context.    or    ADODB.Recordset error '800a0c93'  The operation requested by the application is not allowed in this context.    or    ADODB.Recordset error '800a0c93'  Illegal Operation.

 
If you are using an ADODB.Recordset to UPDATE / INSERT (e.g. using the AddNew method), use a direct SQL statement instead (see Article #2191). If using SQL Server, use a stored procedure (see Article #2201). 
 
If you are using a DSN, try using an OLE-DB, DSN-less connection (see Article #2126). 
 
If you are attempting to use MovePrevious on a forward-only / default recordset, consider the requirement again... why would you need to MovePrevious? If the records are ordered 'backwards', change the query to reverse the ORDER BY. If you absolutely must use MovePrevious, then consider using an AdOpenKeyset recordset. 
 
If you are using ADO constants such as 'AdOpenDynamic', make sure you've included ADOVBS.inc (however read Article #2112 first). 
 
If you are trying to 'page' through a recordset, using AbsolutePage and PageSize properties, see an efficient alternative in Article #2120. 
 
If you are trying to binaryWrite image data to an ASP page that also has plain text content, consider retrieving this data in a separate file and pointing to it via <IMG SRC>. You can also see KB #276488 for ways to use ADODB.Stream to return binary content from a database, without using the GetChunk method.