VSConstants.VS_E_BUSY Field

A constant returned by interfaces to asynchronous behavior when the object in question in already busy.

Namespace:  Microsoft.VisualStudio
Assembly:  Microsoft.VisualStudio.Shell.11.0 (in Microsoft.VisualStudio.Shell.11.0.dll)

public const int VS_E_BUSY

An example is starting a build while a project configuration object that can be built is in the process of completing a build or checking time stamps on component files.