Can't open a recordset with recordlocks argument

[mdav2]

I am tring to open a recordset that allows pessimistic record locking. It returns the error "INVALID ARGUMENT" when running the "set rstSender..." line. The code will open the recordset if I remove the "dbPessimistic" from the statement (along with the commas).

Any help would be most appreciative.

' This creates the recordset
Dim dbs As Database
Dim sqlstr As String

' rstSender is declared as a public recordset
' The rstSender recordset is a based on the t_person table details
Set dbs = CurrentDb
sqlstr = "SELECT * FROM letter"
Set rstSender = dbs.OpenRecordset(sqlstr, dbOpenDynaset, , dbPessimistic)

 

[mdav2]

I have discovered that you need to pass a 0 into the options argument for this to work.

Pessimistic locking also seems to lock the whole recordset, not just the record.

Does anyone know if it is possible to have a recordset that you can lock single records on?