Recently Microsoft announced the new version of .NET Framework 4.0 online installer, which means in order to install .NET 4.0 you must be connected to internet to download necessary file for the installation.
A full offline setup called Standalone Installer has been released by Microsoft and is available for download. You can now easily install .NET 4.0 without internet connection and even on multiple PC’s. The redistributable package updates the previous version to the latest .NET Framework 4:
Supports x86, x64 and ia64 architecture platforms.
Download .NET 4.0 Offline Installer [41.8MB] via WebTrickz