Microsoft is looking to please Wednesday as it kicks off its annual BUILD developers conference in San Francisco with the launch of a retooled version of its Windows 8 operating system.

Company executives will take the stage at noon Eastern for a conference keynote, which the firm also is live-streaming on its Channel 9 community site.

Windows 8, launched last fall, was a major departure from the company’s traditional OS. Not only did Microsoft try a new, tile-based and touch-friendly design for the new system, it also split the Windows 8 system into two related versions: Windows RT, which only runs tablet apps, and the full version, which runs PC programs.

Adoption has been fairly slow for Windows 8 — it’s still under five percent, according to Net Market Share — making some people question whether Microsoft’s big redesign bet will be seen as a Vista-like flop.

Eager to head off that narrative, the firm is addressing some of the biggest criticisms of the operating system with an update that will be available for download starting Wednesday. Perhaps the most notable of these changes is the return of the old Start button, which took a brief leave of absence with Windows 8.

CNET reported that users will have the option to shut down or reboot with a right-click. Right-clicking also appears to bring back some, though not all, of the functions from the old Start menu.

Users also will be able to bypass the tiled Windows 8 start screen, which was designed to offer easy access to users’ favorite or most-used programs, in favor of alternate screens such as the traditional desktop.

Microsoft also has added a few more personalization options, meaning that users can set their own images for the Start screen background and move app tiles on the screen more easily. In addition, there are new search features, the ability to save things directly to Microsoft’s cloud-based storage service SkyDrive, and the option to change what the hot corners in Windows 8 do.

The firm announced several of these changes in a May blog post, and even showed off a couple of them at the Computex conference in Taipei earlier this month. At that conference, Microsoft officials announced that Microsoft would include the tablet-version of Outlook as part of the Office suite for Windows 8.1 RT devices.

The company, as ZDNet’s Mary Jo Foley reported earlier this month, has confirmed that the upgrade will be free for all existing Windows 8 users.

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