Microsoft has announced that Vista Service Pack 1 has been released to manufacturing - but it's being held back from public release until mid-March.

Microsoft claims a series of driver issues is preventing the company from offering the Service Pack for download immediately.

As a result, Microsoft will now tweak Windows Update so that systems running the faulty drivers don't download Service Pack 1. "While we know that most customers who update from Windows Vista to SP1 will NOT be affected, our approach is to improve the experience for all our customers," says Nash.

"To do this, we will begin making SP1 available through Windows Update in mid-March, giving us time to work with some of our hardware partners to make adjustments to the installation process for the affected drivers."

Microsoft will then start delivering SP1 to Vista users running automatic updates in mid-April, but once again, those people with the faulty drivers will miss out. "As updates for these drivers become available, they will be installed automatically by Windows Update, which will unblock these systems from getting Service Pack 1.