So... The issue I am currently having first: Unidentified network/No network access.

I've been using the current powerline adapter(NETGEAR XWN5001) to access the router located downstairs for approximately 6 months. I do not use the WIFI option at all and exclusively use the wired setup of the adapter.

Three days ago, the aforementioned issue started occurring after a night's worth of computer shut down. I turned the computer on, Local Area Connection was stuck "identifying" for GOOD 2-3 minutes, after which it turned into Unidentified network/No network access that I am suffering from. I tried the most basic(and the only) fix I know of, which is unplug everything, wait 2 minutes, power on modem->power on router->plug in adapter downstair->plug in adapter upstair->turn on DESKTOP. Unfortunately, this did not change a single thing(As I relied on this "fix" for decades, I attempted this method at least 5 times hoping the next try would magically fix everything).

The main problem is that I do not know which part of the "network map" is broken... My setup goes: Wall->Modem->Linksys E900 Router->XWN Adapter(downstairs)->XWN Adapter(Upstsairs)->Desktop. I'm fairly certain that this is not a modem/router issue since I can connect to the internet(with very feint signal) using the desktop's WIFI to access the router(with or without the adapters plugged in). So the problem must be within the powerline adapters, right?

However, what perplexes me the most is this: When I access the router using the WIFI, the XWN5001 appears as one of its DHCP clients on LAN interface with an assigned IPv4 Address. When I access the XWN5001 adapter itself using the IPv4 address(typed in browser), it says that its LAN port has IP address, DHCP turned on, and SUBNET mask+gateway IP address are also visible. Doesn't this mean that there's a working connection between the router and adapters?

I can connect to neither the router nor the adapter without WIFI enabled(Shouldn't I be able to if there's a working connection between the router and adapters since everything is wired?).

So... I'm at my wit's end. The modem connects to internet fine, the router seems to work fine(connects to internet via WIFI as mentioned), router seems to be connected to adapters and assign their IP addresses fine, adapter seems to be connected to the computer via ethernet cable fine(I can connect directly to modem with powerline adapters and internet works), but somewhere along the line, the assigned IP address is lost and ipconfig returns APIPA IPv4 address(169.254.x.x) with blank default gateway value when I try ipconfig /all.


Your insight would be greatly appreciated....

Edit: Should've included things I've tried since two days ago(Problem's going on for three):

1. Restart modem/router/adapters/computer
2. Reset TCP/IP Stack with https://support.microsoft.com/en-us/kb/299357 (Actually tried both manual and microsoft fixit)
3. Disable/Enable the LAN adapter
4. Disabled Anti-virus/Firewall
5. ipconfig /release and /renew as administrator ( /renew says "An error occurred while renewing interface Local Area Connection : unable to contact your DHCP server. Request has timed out.")
6. Attempted updating router+adapter firmwares (Both say they are already up to date).
7. Checked DHCP Client service to ensure that it is "Started" and "Automatic." Please clarify this
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My setup goes: Wall->Modem->Linksys E900 Router->XWN Adapter(downstairs)->XWN Adapter(Upstairs)->Desktop.