I don't know if this is appropriate here. I am setting up a subscription button in my client's site. As you might have guessed, I wanted to test everything thru sandbox first. I have two sandbox accounts, one for the buyer and the other for the merchant. I created a button using the premier account. I embedded it in a page, set up an handler which was perfectly working when I tested it with sandbox's test tools. However sandbox won't let me in. It always says, "The email address isn't available. Please try again later" or something like that. I am always stuck at the login process after clicking the subscription button. I am lost. Any help pls...