Consolidated List Of Fixes For Error_Internet_Cannot_Connect

[Jezna]

I'm putting this here because I had this error, and upon searching for the solution, found a good dozen possible fixes that worked for some people and not for others.  This list is not in any particular order, and there is very likely some clue as to which fixes to try first in the error messages in the launcher files.

 

"ERROR_INTERNET_CANNOT_CONNECT"

From ADMIN, not specific to this error.
https://forums.warframe.com/index.php?/topic/49657-login-failed-here-is-a-quick-way-to-self-diagnose-and-solve/

During this entire process, keep checking your %localappdata%/Warframe launcher and EE files!

=>  Sometimes just restarting your launcher multiple times or waiting a while works.  This error may be occuring because Warframe really isn't available, or because your own connections are temporarily waltzing into the sunset.  
=>  Start everything as administrator
=>  Check your Firewall for allowances.  Uninstalling Warframe and reinstalling with Firewall off (which made me cringe while I attempted it) apparently worked for a few souls.  Double-check that the allowances cover the Launcher.exe, Warframe.exe, and Warframe.64x.exe (the last two are found in your steam/SteamApps/common folder).  
=>  Check your IE settings, that you are not in offline mode and that your LAN settings (Internet Options > Connections > LAN Settings) are set to automatic detect.  In (Internet Options > Advanced) there is a full Reset option that will require you to restart your computer, if you've made a lot of changes over the years and want to be certain.
=>  Check your Anti-Virus exceptions.  Some Anti-Virus programs come with their own Firewall (which can interfere with Windows' and vice versa)
=>  Uninstall and reinstall
=>  Verify cache (via the Launcher, upper right-hand corner, the gear icon)/defrag
=>  Verify integrity of game cache (Steam).
=>  Start your launcher, then ctrl-alt-del to Start Task Manager and end the process, and then restart launcher.  I have no idea why this worked for someone, but it did.
=>  Make sure that ports are forwarding correctly (portforward.com was a blessing, here)


Further Notes:  Because none of the above worked for me.

My %localappdata%/Warframe etc location didn't have an EE.file even with show hidden files, and the entire /Warframe folder disappears if I exit the location until I restart Warframe.  This led to show another problem; no one likes IE.  No one.  So when your IE kicks the bucket (which is why we all hate it), you don't notice, because you have it disabled or out of sight, out of mind, etc etc.  Since the first thing I do when I reinstall/install Windows is open IE to download Mozilla and then never open IE again, I didn't notice that my IE11 no longer connected to the internet, which means I couldn't try Warframe's IE fix.

IE11 has compatibility issues, from the look of things, due to Windows 8.  Rolling back to IE10 fixed IE not connecting to the internet, and an EE.file started showing up in my %localappdata%/Warframe.  A 'login' window popped up over the Launcher and the ERROR_INTERNET/etc message never appeared, although the login prompt was also unable to connect.  

New error message appeared in the %localappdata%/Warframe/launcher file that hadn't been there before: ERROR_INTERNET_SEC_CERT_REV_FAILED

=> Internet Options > Advanced
=> Uncheck "Warn about certificate address mismatch", "Check for publisher's certificate revocation", "Check for sever certificate revocation" (Fix by UfoL on Steam forums).

My Warframe launcher was fixed at this point and I was able to play the game.