(CNN) -- Microsoft's rebranding of the widely used but culturally fading Hotmail service is off to a big start.
More than 1 million people signed up for e-mail accounts with Outlook, the new service to which all Hotmail users will eventually be transferred, in its first few hours of existence Tuesday.
But one important person apparently didn't, at least not using his full name in his address: Microsoft CEO Steve Ballmer.
Staffers at the PC Pro website were able to register firstname.lastname@example.org.
They weren't the only ones to notice the apparent quirk.
One Twitter user also claims to have secured email@example.com.
"[C]an't wait to see all the spam I get," he wrote.
But it was the Ballmer grab that turned heads. It quickly led to the parody Tumblr account, Ballmer on Ballmer, on which spoof e-mails from the CEO are posted.
In one, the phony Ballmer sends a photo to an account made to look like it belongs to the former Microsoft CEO, philanthropist Bill Gates. The fake Gates' response?
"Would you please not bother me with this s---? I am trying to cure Malaria."
The jokes do highlight at least one positive for Microsoft, though: People in the tech world are talking about Hotmail (or at least its replacement). The e-mail service has long remained the world's most popular, largely due to it being bundled with the near-ubiquitious Windows operating system.
But it had long since lost its cachet with younger or tech-industry users, and by some accounts has been surpassed by Google's Gmail.
But some early reviews of the new Outlook e-mail service have been glowing.
"After a decade as a punchline, Hotmail just pulled off the biggest victory in the inbox game since Gmail. And it might just get you to switch," wrote Sam Biddle on Gizmodo.
Shortly after 3 p.m. ET Tuesday, the Outlook Twitter account posted a chart showing the million sign-ups.
Right now, switching to Outlook is voluntary for Hotmail users. They'll eventually have no choice, although Microsoft has not disclosed a timetable for that move.