主题：[求助]狐表开发的软件是不是不支持WIN2008？

在WIN7下同样是64位系统 但是win7下没有问题 但是到了WIN2008刚打开软件就弹错

.NET Framework 版本：2.0.50727.5420
Foxtable 版本：2015.12.22.1
错误所在事件：项目,AfterOpenProject
详细错误信息：
从类型“DBNull”到类型“String”的转换无效。

请问是什么问题啊

'下面是错误代码，要怎么改呢

Dim l1 As String
Dim l2 As String
Dim l3 As String
Dim l4 As String

With HardWareInfo.CPU
    l1 = .ProcessorId
End With
With HardWareInfo.Disk
    l2 = .Signature
End With

Dim WMI As object = GetObject("WinMgmts:")
Dim disk1 As object
Dim mn,sn As WinForm.Label
For Each disk1 In WMI.InstancesOf("Win32_diskDrive")
    l3  = disk1.Model
    Exit For
Next
For Each disk1 In WMI.InstancesOf("Win32_PhysicalMedia")
    l4  = Trim(disk1.SerialNumber)
    Exit For
Next

Dim s1 As String
Dim ss As String() ={"a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z","A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"}

s1 = l1 &  l2 & l3 & l4
s1 = s1.Replace(" ","")
For Each i As String In ss
    s1 = s1.Replace(i,"")
Next
Vars("序列号") = s1
Vars("注册码") = byst

byst = (DecryptText(byst.Replace("_",""),"a","t")).Replace("#","")
'''
If byst = s1 Then
    Vars("开关") = True
End If

If Vars("开关") = True Then
    Vars("状态") ="已注册"
Else
    Vars("状态") ="未注册"
End If
'''