Microsoft said it has fixed a Vista SP1 reboot bug that had caused some users to suspend migrations and that the revised software will again be offered via automatic distribution.
The Vista Servicing Stack Update (SSU) was a prerequisite for installing Vista SP1 via Windows Update that was made available by Microsoft in February. The software, designed to ease installation, instead had the opposite effect by throwing some users into an endless reboot cycle.
At the time, Microsoft called negative reaction to the issue "a feeding frenzy."
Microsoft says the problem is fixed and it will again offer the SSU prerequisite code starting April 8th. Users who have already successfully installed SSU do not need to reinstall it. In addition, users who have a copy of SP1 acquired by any means other than Windows Update do not need to install SSU.
Microsoft is fixing the problem by issuing a fix that installs prior to the installation of the SSU, a prerequisite for the prerequisite.
The new piece of code will ensure a "smooth install of the SSU by working to prevent the system from rebooting during the SP1 SSU installation," according to the Microsoft Product Update Team Blog. The blog also says Microsoft made additional changes to the SSU installer code that will ensure the pre-SSU is installed before it attempts to load SSU.
The company said the original problem occurred during some "unknown and rare" instances when the SSU thought it needed to reboot when it did not. The resulting reboot try then touched off a never ending cycle of attempts and failures.
Microsoft says users with Windows Update activated do not have to take any action before April 8 to receive both the pre-SSU and the SSU code.