How to execute a stored SQL procedure in Microsoft Excel?

This is a job for an ADODB connection in VBA. Here's a link with a sample code for a simple SELECT query, but this will handle stored procedures just as well.

http://www.ozgrid.com/forum/showthread.php?t=83016&page=1

The key items are the need to declare an ADODB.Connection, ADODB.Recordset, and a connection string that matches your database. After opening the connection, you execute your SQL statement using syntax like the following (taken from the link):

With cnt 
    .CursorLocation = adUseClient 
    .Open stADO    // stADO is the connection string.
    .CommandTimeout = 0 
    Set rst = .Execute(stSQL) 
End With

Then move the data from your recordset (rst, above) into a range using Range.CopyFromRecordSet.