SSIS: Invalid access to memory location

Windover House, Saint Anne Street from Wilts Arch and Nat Hist MagProblem came up trying to connect to a remote Oracle source:

Started: 12:03:03
Error: 2013-10-09 12:03:03.84
Code: 0xC0202009
Description: SSIS Error Code DTS_E_OLEDBERROR. An OLE DB error has occurred. Error code: 0x800703E6.
An OLE DB record is available. Source: "Microsoft OLE DB Service Components" Hresult: 0x800703E6 Description: "Invalid access to memory location.".
End Error
Error: 2013-10-09 12:03:03.84
Code: 0xC020801C
Source: Copy Data
Description: SSIS Error Code DTS_E_CANNOTACQUIRECONNECTIONFROMCONNECTIONMANAGER. The AcquireConnection method call to the connection manager "xxx" failed with error code 0xC0202009. There may be error messages posted before this with more information on why the AcquireConnection method call failed.
End Error
Error: 2013-10-09 12:03:03.84
Code: 0xC0047017
Source: xxxx
Description: component "xxx" (1) failed validation and returned error code 0xC020801C.
End Error
DTExec: The package execution returned DTSER_FAILURE (1).

Fix was to go into job step properties, select the ‘Execution options’ tab and click on ‘Use 32-bit runtime’.

I’m wondering whether we had an Oracle 32-bit install, or a 32-bit install that wasn’t entirely removed