Before installing WaspTime Web, the following items should be enabled. On Windows client versions (7, 8, 10), they're in "Turn Windows features on or off" inside the Programs and Features control panel. In Windows Server these are accessed via Server Manager.

.NET 3.5.x
.NET 4.x

IIS Features:
ASP
ASP.NET
Server Side Includes
IIS 6 Scripting Tools (or IIS Management Scripts and tools on Windows 7/Server 2008)
IIS Management Console