Stylus Linking Issue
If your Windows stylus / pen is not working in ArcSite while on a Microsoft Surface or Windows device, the issue may be related to a setting that needs to be toggled off in Microsoft Pen & Ink Settings within the Bluetooth settings menu.
Steps
Open Windows Start Menu
Open Settings app
Open the Bluetooth and Devices option
Open the Pen & Windows Ink option
Open the Additional Pen Setting option
Ensure the the Let me use my pen as a mouse option is toggled off
Unexpected Touch Inputs Issue
If you are using ArcSite with a stylus on a Microsoft Surface, and sometimes experience unexpected touches, the issue may be with the device thinking your palm is a touch input.
You can toggle the setting to ignore touch inputs when using the pen in the Windows Settings.
Steps
Click on the Start menu
Select Settings
Choose Devices
Go to Pen & Windows Ink
Turn on Ignore touch input when I'm using my pen