Omnet ++ Download and Install for Windows
1. Go to https://omnetpp.org/download/ choose your operating system and click download.
2. Copy the OMNeT++ archive to the directory where you want to install it. Choose a directory whose full path does not contain any space;
3. In the new omnetpp-5.5 directory, you should see directories named doc, images, include, tools, etc., and files named mingwenv.cmd, configure, Makefile, and others.
4. Configuring and Building OMNeT++
Start mingwenv.cmd in the omnetpp-5.5 directory by double-clicking it in Windows Explorer. It will bring up a console with the MSYS bash shell. On the first start of the shell, you may need to wait for the extraction of the tools directory.
Add OMNeT++'s bin directory and also the bin directories in the tools folder to the path;