How is this error possible?

[Edwin Knoppert]

Unable to cast COM object of type 'System.__ComObject' to interface type
'IRowset'. This operation failed because the QueryInterface call on the COM
component for the interface with IID
'{0C733A7C-2A1C-11CE-ADE5-00AA0044773D}' failed due to the following error:
No such interface supported (Exception from HRESULT: 0x80004002
(E_NOINTERFACE)).

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This is an exception i get when i try to create an XLS file via OLEDB.
The 2nd button > click event > generate xls works fine.
In fact it works almost always.
??