It is when you are using IPV6:
https://en.wikipedia.org/wiki/IPv6[
^]
IPV4 is the protocal you're thinking of. See if the list in
Dns.GetHostAddresses(Dns.GetHostName())
has one. If there are both the your code just writes over the label and leaves it with the old one.
You can test this by changing the label line:
label2.Text += adress + ", ";