When the application first starts, you will be at the "General" tab for the Windows section.
If you are on some other operating system, none of these functions will work. However, if you are on Windows, then the following functions will be of use to you.
The next tab for Windows is the "Networking" tab.
Here, you will have various tools that will allow you to troubleshoot most network issues you may have. Again, the functions here will not work if you are not on Windows.
The final tab for Windows is the "Virus/Malware Removal" tab.
This section will provide you links to download the main malware removal tools used by the ITU, as well as open them if they are already installed on your system.
The "Mac" tab will provide you links to the various maintenance tools available for Macintosh systems, as well as a link to the support forums should the tools not resolve your issues.