Microsoft's upcoming Internet Explorer 7 will run on other operating systems besides Windows XP SP2, the company's official IE blog revealed Monday, but Windows 2000 remains off the list.

In mid-February, chairman Bill Gates promised a new version of IE before Longhorn ships, and said the new browser -- which will concentrate on delivering additional security against such threats as phishing -- would roll into beta this summer. At that time, only Windows XP SP2 was mentioned as a supported OS.

According to the posting on the blog, IE 7 will also work on the 64-bit edition of XP (with the long title of "Windows XP Professional x64 Edition") and the upcoming Windows Server 2003 Service Pack 1 (SP1).

About Windows 2000 support, Microsoft hasn't budged from its previous position. "We have heard the requests for support of Windows 2000, but have nothing to announce at this time."

On a related subject, the blog also made clear that a new version of Outlook Express, Microsoft's for-free basic e-mail client, would not appear with IE7. "There are no plans to ship the new version of Outlook Express before the next release of Windows," stated the blog.

The next edition of Windows will be Longhorn, which isn't expected until 2006 at the earliest.