Error In ASP Application

I just inherited two ASP applications from someone here at work. ASP is not my strong suit One of them seems to work fine, but the other one gives this error when I first set it up.

The error is:
Microsoft OLE DB Provider for ODBC Driverserror '80004005'
[Microsoft][ODBC Microsoft Access Driver] Operation must use an updateable query.
/mary/technet/scripts/sched/phonesa.asp, line 34

The code that it references is here:
SQLStmt = "UPDATE inout SET inout.yesterday = Date(), inout.inorout = 0 "
SQLStmt = SQLStmt & "WHERE (inout.yesterday)<> #" & myDate & "#"
Set RS = Connection.Execute(SQLStmt)
if CheckRS(RS) Then
set RS = Nothing
End If

The database is an old version of Access and I do not have Access installed on the server, but the other application works and it is in Access too. I don't understand the issue,