Welcome to the community. 
If you’re using Windows, you have an antivirus. It’s called Windows Defender and it cannot be removed because it is permanently embedded into the operating system.
Failed installations are, the majority of the time, caused by interference from security programs on your machine or network.
Take a look at this thread for troubleshooting: I can’t Install WeMod / “There was a error installing the application” - WeMod App / Support.