obj mail

hi guys,
I've created a COM which simply sends an email; on my PC it works well. However, when I tested it on the server, I've found out that that server has got outlook express installed instead of outlook, thus my code doesn't work!!!
Does anybody knows how can I change my code to make it work also with outlook express? ( I 'm not allowed to install outlook on that server).

N.B references checked are DAO and Outlook

here my code
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'--- mail
Dim objOutlook As New Outlook.Application
Dim objOutlookMsg As Outlook.MailItem


'Create new message
Set objOutlookMsg = objOutlook.CreateItem(olMailItem)

With objOutlookMsg
.To = destinatario
.Subject = titolo
.Body = corpo
.Importance = olImportanceHigh
.Send
End With

Set objOutlookMsg = Nothing

'Close Outlook instance: Important!
Set objOutlook = Nothing

'--- mail