For over 5 years, I've run the same network in my home.
My personal computer receives it's signal from a custom-built antenna with attached ampliflier, which gives my internet signal directly to my machine; the internet source is from my parents' house (I live in a neighboring home).
The internet on my machine works just fine, like usual; however, I recently went on vacation and took my computer with me and upon return my network now fails. I used a direct ethernet link for internet during this vacation. This situation has happened before, but I previously fixed this problem with a system restore; this is no longer an option because I don't have the option to restore to a point before I was gone on vacation. When I say this happened before, I mean everything about this problem is identical to the time I encountered it last, that my network router remained visible and the internet worked on my main computer, but the router wouldn't 'take' the signal and broadcast it properly.
The problem as best as I can understand is this: the router is visible and is directly connected to my personal computer; however, there is no internet signal when connecting to the router via phone, laptop, etc. The only message that suggests something is wrong is the following: Local Area Connection does not have a valid IP configuration. When trying to connect with her laptop, my girlfriend received this message and also when trying to diagnose my local area connection I received the same message about the IP address being invalid for the Local Area Connection.
What could be wrong? When this happened before, my friend who works in IT explained that since normally you receive internet from routers and not vice versa (I'm trying to get my router to broadcast the internet signal that my computer already has) that the diagnostics behind it can be difficult and thus only did a system restore.
I'm completely in the dark as how to fix this. Nothing is wrong hardware-wise, I am sure of this. I read about trying to reset ip settings for ipv4/ipv6 through cmd, but nothing has worked so far.
System specs updated