数据库同时被打开的时侯,提示"不能锁定文件"!

最近用 VB编程实现打开access数据库查询的操作.单次执行没有问题, 但是如果同时多次调用此程序总会出现80004005的错误代码,并提示"不能锁定文件"

我在access选项中设置的是共享的形式.不知为什么会报这个错!请大侠知道啊!!!!

VB代码如下: 测试了一下,这个错误总是在dbconn.open 时发生的!

public function GetPasswd()

Set dbconn = New ADODB.Connection
dbconn.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:\Doc\hostmonitor\VBS\passwddb.mdb;Persist Security Info=False; Mode= Share Deny None"
Dim sql As String
sql = "select * from tb_passwd"
dbconn.Open

Set dbrs = New ADODB.Recordset
dbrs.Open sql, dbconn, adOpenForwardOnly, adLockOptimistic

Dim name As String
Dim ip As String
Dim found As Boolean
found = False

Do While Not dbrs.EOF
        ip = dbrs.Fields("ip")
        name = dbrs.Fields("name")
        If ip = IPAddr And name = UserName Then
            GetPasswd = dbrs.Fields("passwd")
            found = True
            Exit Do
        End If
           
        dbrs.MoveNext
Loop
dbrs.Close
dbconn.Close
End Function