Microsoft has already prepared Windows 7 with code to let users download the new operating system's first service pack, a prominent blogger reported last weekend.
A first service pack -- which includes already-issued security patches as well as new bug fixes, and in some cases, new features -- is important because many corporations won't widely deploy a new edition of Windows until that milestone has been reached. Service packs are also relatively rare: Windows XP, which debuted in October 2001, has had only three.
Rivera took the appearance of the eligibility check to mean that SP1 testing is imminent. "The takeaway here is that external [emphasis in original] Windows 7 SP1 testing should commence soon, if it hasn't already," said Rivera.
But even if Rivera's hunch is correct, it could be months before Microsoft launches a public preview of SP1. For example, although Microsoft seeded an invite-only group of testers with Vista SP1 in September 2007, it didn't make the beta available to the general public until December 2007.
Microsoft has embedded similar keys in Vista, as well as Windows XP, to determine who is eligible, and when, to receive a service pack beta via Windows Update. In the cases of both Vista and Windows XP, Microsoft offered small downloads when it was ready to expand the preview to the public; those downloads modified the registry so users' PCs would "see" the service pack on Windows Update.
If Microsoft adheres to the timeline it used for Vista, Windows 7's SP1 should be available to a small group of testers in June, and to the public in September.
This isn't the first time that Rivera has rooted out details of Microsoft's software. Last November, Rivera accused Microsoft of using open-source code in a Windows 7 installation tool without acknowledging where it got the code. Microsoft quickly pulled the Windows 7 USB/DVD Download Tool, then later re-released it as open-source.
Microsoft declined to answer questions about its Windows 7 SP1 plans, or comment on Rivera's discovery of the eligibility keys in the operating system's registry. A company spokeswoman would only say, "Microsoft makes it a practice not to comment on rumors or speculation."
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter @gkeizer, send e-mail at email@example.com or subscribe to Gregg's RSS feed .