A lot of work was done in Windows 10 to support high resolution screens, such as the Surface Pro 3, Surface Pro 4, Surface Book, and third-party laptops and tablets with screen resolutions above 1080p. However, there are issues that occur when using Office apps on these devices when connecting to an external monitor with a lower resolution.
Office apps such as PowerPoint, Skype or Skype for Business display very large or very small
You have blurry text in your Office applications
The Office applications do not yet support an external monitor with a different resolution where you have more than one monitor at a different resolution.
Upcoming improvements and possible solutions until the update is released
Microsoft is aware of the problem and is actively working on improving this in Office 2016.
Now available, you can see the following improvements when running Office 2016 on Windows 10 version 1607, also known as the Windows 10 Anniversary Update.
Enable system scaling for PowerPoint 2016 on Windows 10 version 1607. The current issue of PowerPoint not automatically scaling to different monitor sizes when in edit view is addressed with Windows 10 Anniversary Update (Version 1607). With the updated fix, PowerPoint will adjust to the correct screen size when dragged to different monitors. To access this fix, customers must have Windows 10 version 1607 or later, and PowerPoint version 16.0.7341.2032 or later. PowerPoint version 16.0.7341.2032 was released on September 21, 2016 for Current Channel customers. For more information on how to install the latest update for PowerPoint, go to Install Office updates
Enable system scaling for Skype for Business 2016 on Windows 10 version 1607. The current issue of Skype for Business 2016 not correctly scaling when your screen resolution changes is addressed with Windows 10 Anniversary Update (Version 1607), and an accompanying Skype fix. With the updated fix, Skype will adjust to the correct screen size when docked or undocked or when being dragged to different monitors. To access this fix, you must have Windows 10 version 1607 or later, and Skype version 16.0.7369.2024 or later, released on October 4, 2016 for Current Channel customers. This scaling issue is planned to be fixed for Lync 2013 and Skype for Business 2015 in the Office 2013 November update and later for other channels of Skype for Business 2016.
Some of the longer term items being worked on include:
Enable per monitor awareness and app scaling for Skype for Business 2016. We are investigating the scope of work to make Skype for Business a true per-monitor aware app. The work depends on Office infrastructure changes that are under development.
Enable per monitor awareness and app scaling for Office apps. We are actively working on the user interface platform for Office Win 32 apps to enable Office apps to be true per-monitor aware apps.
Enable system scaling for PowerPoint and Lync. System scaling for these two apps as part of Office 365 or 2016 for MSI will be available at a later date.
The workarounds for this issue are limited. Below are some potential workarounds that may or may not help.
Applications do not scale well: This might be corrected by logging out, and then logging in to your Microsoft Account or Office 365 work or school Azure Active Directory account. You can determine if this is necessary by checking the display settings (Control Panel > Appearance and Personalization > Display) for each monitor. If it shows "Some apps won't respond to scaling changes until you sign out" you must sign out and then sign in to correct the scaling.
Change display settings: You might be able to change the behavior by doing the following: Open Display settings and modify the setting for "Change the size of text, apps, and other items" for each monitor (Windows 10 only).
More information about this issue is in the following links: