用户定义类型未定义

Dim ConnX As ADODB.Connection'生成连接字符串
ConnX.ConnectionString = "Provider=SQLOLEDB.1;Persist Security Info=False;User ID=sa;password=jnjw2008;Initial Catalog=tygl;Data Source=192.168.0.119"

On Error GoTo ConnErr
    '连接数据库
    ConnX.Open
    MsgBox "连接数据库成功！", vbInformation, "连接"
    Exit Sub
ConnErr:
    MsgBox "连接数据库错误！", vbInformation, "连接"
我用的是vb6.0出现错误：编译错误，用户定义类型未定义   该如何解决请高手指点！！！！谢谢！！！