Hi again, I wanted to say that it's been very stable; still no issues at all.
I think it happened because I didn't reset the NVRAM properly before and after flashing the router, but now I do it every time.
I even have CTF + CTF & FA enabled; it is very stable, and I get full Gigabit speeds.
Got my hands on more routers and two more R7000 routers. Such good routers, especially with DD-WRT on them.
I'm very happy with DD-WRT; it allows to do great things. Thanks!
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*I also have some interesting information from my latest experiments:
"Windows Security+Firewall Interfering-Router Firmware Upgrade.txt"
"I could only flash my 2nd Netgear R7000 router using nmrpflash, no matter which firmware I wanted to flash (Netgear stock or DD-WRT).
I wanted to be able to flash it from its UI.
I backed up its CFE, compared it with the others I have, and flashed a CFE from another R7000.
It still had the same behavior when trying to flash from its UI. It wasn't caused by its CFE, so I flashed it back.
Except for that, everything seemed fine with this router and my hardware.
The only possible cause left was my Windows 10 operating system and my Google Chrome web browser.
*Same behavior with Windows + Firefox, so why not try with Linux at this point?
I successfully flashed it from its UI using Firefox on a Linux Mint Xfce LiveCD instead of Windows + Chrome.
This reminds me of an old IP camera I could only view with Linux Mint Xfce + Firefox but not with Windows + Chrome.
Disabling the firewall in Windows didn't help, but it is recommended.
I disabled Windows Security and successfully flashed it from its UI using Google Chrome. (It also worked with Edge and Firefox.)
*I turned off every option in Windows Security to make sure it works.
*DD-WRT recommends disabling the antivirus (Windows Security) + firewall after going offline, then restoring everything before going back online.
Update:
Windows Security tends to re-enable itself, especially after rebooting.
Firmware flash succeeded once again but failed twice, even with Windows Security + Firewall disabled.
Not sure why it happens only with this one, but using Linux + Firefox for flashing seems to be a much safer option.
I could also flash every other router using Linux from now on because it works great as well."
