Microsoft has reversed field and opened public access to the latest beta build of Vista Service Pack 1. Users can now download Vista SP1 RC Refresh from Microsoft’s Web site. Users can install the beta via Windows Update, but Microsoft is providing a list of procedures users should follow to avoid problems.

While the company released the tweak on January 9, it originally restricted the download to approximately 15,000 steely-nerved beta testers. Two days later, the company was feeling more adventurous. Microsoft posted on Friday the latest code for open public consumption on its website along with a set of instructions for installing the update.

The refresh requires the same time-consuming, multiple-reboot process used by Vista SP1 RC in December. Also, users who have uninstalled that version must wait an hour before beginning the laborious update. “The installer service needs to clean up and complete the uninstall prior to installing the RC,” said instructions posted on the Web. “Failing to do this can result in installation errors when installing the RC version.”

Refresh is time-limited, with the deadline for uninstall being June 30, 2008. According to Foley, Microsoft still aims to have the official version of SP1 available within the first quarter of 2008.

On its Web site, Microsoft warned that it “does not recommend installing this software on primary or mission-critical systems.”

Click here to access the SP1 RC Refresh