Microsoft today took the unusual step of telling users running Windows 10's Technical Preview to uninstall Office before applying one of December's security updates.

"We just made a tough call after working through the night that I thought I should share with you," wrote Gabe Aul, the engineering general manager for Microsoft's operating system group, in a four-part Twitter understatement Tuesday.

"We have a security update going out today, and the installer fails on 9879 if Office is installed," Aul continued. "Rather than rolling a new fix (losing several days in the process) we're going to publish it as is. The workaround is painful: uninstall Office, install the hotfix, reinstall Office. Sorry. We're working hard to fix."

Aul's mention of "9879" referred to the latest "build" of the preview; Microsoft issued Build 9879 four weeks ago.

Somewhat later, Aul identified the update as KB3022827, the Knowledge Base identifier displayed in Windows Update on the preview. (Computerworld was unable to find an associated page on Microsoft's support site that matched KB3022827.) He also partly retracted his advice to uninstall Office: "Please try to install KB3022827 before the workaround to uninstall Office first. It will work for many, no harm if not," he tweeted.

Several people chimed in on Aul's Twitter feed to say that they had tried the update before uninstalling Office and had no problems.

According to Microsoft, only one of today's seven security updates was to be applied to Windows 10's preview. That update, pegged as MS14-080, patched 14 vulnerabilities in Internet Explorer (IE) 11, the browser bundled with the OS.

Andrew Storms, vice president of security services at New Context, weighed in on Aul's odd workaround.

"There are always upsides and downsides to being on the bleeding edge," Storms said in an interview conducted via instant messaging. "Users who chose to grab the Windows 10 Technical Preview are now stuck between the proverbial rock and a hard place. Today, Microsoft admitted that some number of their users are plagued with Explorer crashes and what's worse, an update that won't be easy to install. I, like Microsoft, hope that these users are adept enough to figure out the workaround/fix on their own."

As Storms said, Microsoft acknowledged that one in eight users of the preview had been unable to install an earlier fix that was supposed to stop crashes of the operating system's Explorer file manager.

"On a shipping OS, if we hit an issue like this we'd normally pull the update," Aul admitted in talking about the Explorer screw-up. "But since the Windows Insider audience is technical, we decided to leave it up while we work on the fix so that people hitting the Explorer crash can get some relief."

Storms echoed Aul's confidence in Windows 10 users' skills. "Preview users are generally the most willing to nuke and repave their systems," Storms said.

Also Tuesday, Microsoft shipped seven security updates that patched 24 vulnerabilities in earlier editions of Windows, IE, Office, and the SharePoint and Exchange server software.

This story, "Microsoft tells Windows 10 users to uninstall Office" was originally published by Computerworld .