No pc mac or linux build module!!!

Hey, so before anyone gets angry, I know this shouldn't be in the coding category, but I'm in a rush and made a mistake.

So my problem is when I go to build my game (for PC) to test it, it says I have no mac, linux, or pc build modules. I know what this means and I know where I went wrong in the installation, but I'm wondering if I can fix this without reinstalling unity. The reason I care is because it took me about 2 hours to install it the first time (It wasn't "agreeing" with my laptop) and when I tried to install it again today, I couldn't even get it to work.

Any help is greatly appreciated

 

Download the appropriate modules with the download assistant.

--Eric

 

How do I use the download assistant? I have read lots about it, but can't find it in my files, do I have do download it??? I'm confused and probably really stupid sorry

 

https://unity3d.com/get-unity/download?ref=personal

--Eric

 

Thanks but isn't this just reinstalling it?

 

No. Download the download assistant, and run it.

--Eric

 

Whoops, well I think i reinstalled the entire thing, but I was able to do it, and it fixed my problem. Thanks so much for all the quick responses!