Microsoft has released Windows Vista Service Pack 1 Release Candidate to developers.
This is the final stage before Vista SP1 is ready for commercial release in the first quarter of next year.
The Release Candidate will available to the wider public from next week, said Microsoft on its Vista development blog.
Vista product manager Nick White said, "We are on track to complete and release SP1 in the first quarter of 2008."
For administrators managing Windows Vista PCs configured to use Windows Update, but not wishing to deploy SP1 upon its release, there will be "blocker patch" that will prevent installation of SP1, said White.
"We have built Windows Vista SP1 to address specific reliability and performance issues and also to support new types of hardware and several emerging standards," said White.