If I remember correctly, there are two types of addresses available; one comes with a transaction ID combined with it. Any chance you're needing to use one of those?
Wrong wallet adress? Not beginning with "4"
Hello, May be somebody can help me? I tried to send some from mymonero to my Gui wallet. It dosent work, I got the message "invalid adress prefix". When I am checking my adress which I generated with the Gui interface, I noticed that it will not start with with "4". I made a new Gui wallet adress, the same again, without the starting "4". May be there is no "4" I cant send? Some body has an idea, Thanks....