You are advised to update to 15.35 or later, but even that’s no guarantee. Microsoft says that versions 15.34 and earlier are not supported, and you may not be able to launch the apps. It also notes that users of Office 2016 for Mac may experience problems with High Sierra … Word, Excel, PowerPoint, Outlook and Lync have not been tested on macOS 10.13 High Sierra, and no formal support for this configuration will be provided. It doesn’t go as far as to say the software will not work, but hints at this. Microsoft has announced in a support document that Office for Mac 2011 will not be supported under macOS 10.13 High Sierra.