The first error, error 2 is showing that it wasn't able to find .cab file. You only need to do the command on the .cab file, not the contents inside the folder. Could you try re-downloading the file and moving it over to the desktop, and trying the command again? You can just leave the .cab file as is once it's on your desktop, you don't need to unzip anything before the command prompt step.
If that doesn't work, then...
1. On the computer with internet problems, move FRST from the downloads folder to the desktop, then open the tool
2. Copy the following text and paste it into a notepad document, naming it: "fixlist" (without the quotes):
3. Transfer the notepad file to the desktop where FRST is located
4. In FRST, press Fix, and copy/paste the resulting log in your next reply.