Why do I get 800A0E7D errors?

When using the command object to invoke a SQL Server stored procedure, you may have seen this error: 
 

ADODB.Command (0x800A0E7D)  Requested operation requires an OLE DB Session object, which is not  supported by the current provider.    or    ADODB.Command error '800a0e7d'  The connection cannot be used to perform this operation. It is either closed  or invalid in this context.

 
The most likely cause is that you are trying to set the command object's activeConnection to an invalid connection object, or you didn't set the activeConnection property at all. Check over your code, and make sure your connection object is valid and open before trying to set it as the active connection for your command object. Also, make sure you use the SET keyword: 
 

objCmd.ActiveConnection = objConn    ' should be:    SET objCmd.ActiveConnection = objConn

 
Or, avoid using the command object altogether; it is unnecessary for most SP executions from ASP, unless you need output parameters / return values. 
 
Other possible causes include:

• you are using SQLOLEDB, and have forcefully turned off pooling (either in the metabase or by adding "OLE DB Services=-2" to the connection string) — see Pooling in the Microsoft Data Access Com... for details on how to ensure that session pooling is enabled;
• you are *not* using an OLE-DB connection string (see Article #2126);
• you are using a File DSN which IUSR cannot access;
• you lack permissions to connect to the SQL Server;
• you haven't properly defined your ADODB.Command parameters;
• you are explicitly declaring an ADODB.Recordset object when you could be getting by with a simpler invocation (see Article #2191); or,
• you are using an ancient version of MDAC (upgrade to the most recent version at MDAC Download Page).