Hi Renato,
Not sure about IP 2010, I'm using IP 2007 and just did something which fits your description. The code for Visual Basic is:
Dim result As DialogResult
result = MessageBox.Show("Thank you! The form has been submitted successfully." & NewLine & "Your administrator will contact you if further details are required. Would you like to reuse this form to submit a new request?", "Form submitted!", MessageBoxButtons.YesNo, MessageBoxIcon.Information)
If result = DialogResult.Yes Then
MessageBox.Show("Please amend your new request.", "Please amend your form")
end if
You can put this code as a changed event or on a button code. To change your exclamation icon to something informative? Try the Information box icon. Good luck!