The Microsoft Data Access Components (MDAC) support the option of a client cursor engine. This feature is implemented as part of OLE DB, ADO, and Remote Data Services (RDS). When using ADO, a client cursor is enabled by setting the CursorLocation property on the recordset to adUseClient.
The OLE DB Provider for AS/400 and VSAM does not support any updating capabilities when used with a client cursor engine. In other words, if a client cursor engine is enabled using RDS or ADO, the OLE DB provider cannot be used to update data on the host. The ADO recordset is treated as if it were read-only.