Allowing Multiple people

[manofsteel00]

I'm developing an application that interfaces with a database to allow multiple users to select multiple items from an Access database using ADO DB. However, whenever there are multiple users I get a "Run-time Error 339: A File is missing or is invalid". This error happens whenever a form loads and the code for that for is:

'*FORM_LOAD()******************************************************************
'NAME: Form_Load()
'DESC: Initially loads the listbox (lstFirstScreen) with the available data
'      from the database
Private Sub Form_Load()
    cmdSelect.Enabled = False
    lblTopTabs.Caption = "PICKSL" & "     " _
                       & " DFC" & "           " _
                       & "PROD" & "        " _
                       & "DESC"
    
    cmdPrint.Visible = False
    cmdPrint.Enabled = False
    
    Set connection = New ADODB.connection
    connection.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;" & _
        "Data Source= G:\Finance\Inventory Control\CycleCount\DB\cycleCount.mdb"
    connection.Open
    
    Set newConnection = New ADODB.connection
    newConnection.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;" & _
        "Data Source= G:\Finance\Inventory Control\CycleCount\DB\cycleCount.mdb"
    newConnection.Open
    
    Set recordSet = New ADODB.recordSet
    Set newRecordSet = New ADODB.recordSet
      
    Dim inAlterTable As Boolean
    Dim selectStatement As String
    Dim newSelectStatement As String
    
    selectStatement = "SELECT DISTINCT PICKSL,DFP,PROD,DESC FROM [MAIN]"
    newSelectStatement = "SELECT * FROM [ALTER] WHERE TYPEOFCHANGE='SELECTED'"
        
    recordSet.Open selectStatement, connection, adOpenKeyset, adLockPessimistic, adCmdText
    newRecordSet.Open newSelectStatement, newConnection, adOpenKeyset, adLockPessimistic, adCmdText
    
    recordSet.MoveFirst
            
    Do Until recordSet.EOF
        If (newRecordSet.EOF <> True) Then
            newRecordSet.MoveFirst
        End If
        inAlterTable = False
        Do Until newRecordSet.EOF
            If (recordSet.Fields("PICKSL") = newRecordSet.Fields("PICKSL") And _
                recordSet.Fields("DFP") = newRecordSet.Fields("DFP") And _
                recordSet.Fields("PROD") = newRecordSet.Fields("PROD") And _
                recordSet.Fields("DESC") = newRecordSet.Fields("DESC")) Then
                inAlterTable = True
            End If
            DoEvents
            newRecordSet.MoveNext
        Loop
 
        If (inAlterTable = False) Then
            lstFirstScreen.AddItem (recordSet.Fields("PICKSL") & vbTab _
                & recordSet.Fields("DFP") & vbTab _
                & recordSet.Fields("PROD") & vbTab _
                & recordSet.Fields("Desc"))
        End If
        DoEvents
               
        recordSet.MoveNext
    Loop
    
    recordSet.Close
    connection.Close
    Set recordSet = Nothing
    Set connection = Nothing
    
    If (lstFirstScreen.ListCount > 0) Then
        cmdSelect.Enabled = True
    End If
    
End Sub
'*ENDOF*FORM_LOAD()************************************************************

I do have a pessimistic lock on the database; could that be what is causing it. And if so I can I keep users from getting the same data at the same time? Any help you be greatly appreciated.