Can't connect to secure sites with ANY browser or app

OK, I'm on the second day of this.

I CANNOT connect to any secure site, nor can the built-in stuff like signing into my Microsoft account, using the Media Creation Tool or anything that would go through an HTTPS connection. I CAN get to Windows Update for some reason. I cannot even use the search function here on tenforums (it's Google based, and wants the secure connection).

Neither System File Checker or DISM report any problems! (this really baffles me)

I am on my fourth clean install. Same thing has persisted. Note that the iso seems to be OK in all other things, which kind of knocks out corruption there.

On all of my attempts, the TLS settings in Internet Options/Advanced are marked as active.

What I have tracked down: My system, or systems since I've rebuilt this thing so many times, is missing several crucial dlls. The ones I know about are initpki.dll, gpkcsp.dll, sccbase.dll and slbcsp.dll. I have tried reregistering them several different ways. I finally just started searching on my computer for them by name (and I do have the option to check system files ticked) and it appears that they just aren't on any of the installations.

I have reset my modem/router. I have tried searching, but I have troubles there, too - all of the Microsoft forums are behind https addresses, Google also insists on https, and I can search a little on Bing, but most of the sites that come up that are legit also have https addresses.

I have NO idea why these things are not getting installed. And I don't know how to get them on my comp!

I'm using Windows 10 Anniversary Edition (and I don't have a copy of the non-anniversary edition to fall back on). It's Win 10 Pro 64-bit. I'm not using any security beyond Windows Defender (and the problem did not clear up when I turned the firewall off).

All of the reinstalls have been clean - I even used diskpart from the install disk command line to make sure they were formatted and clean and formatted NTFS. This whole mess started when I upgraded and forgot that my User folders were on a different drive. The last time I installed, the second drive was disconnected, so the system shouldn't even be aware of it. (I know, this is probably totally irrelevant, but I'm desperate.)

ANY help would be appreciated. And I'll do my best to answer any questions or follow any links...but remember, I CANNOT ACCESS HTTPS SITES!!!

Thanks in advance. This is weird.

What is your mtu set to Change your MTU under Vista, Windows 7 or Windows 8 richard-slater.co.uk can other pcs on the network get there ok?

1. I have no problems connecting to any site on my Android phone, which goes through the same router.
2. The time and time zone are both right. I've also tried with the time zone set to central (I'm very, very close to the line between Central and Eastern.) No difference.
3. Safe Mode with Networking gave me the same results (I can't connect to any secure site.)
4. The only A/V and firewall I have are from Windows Defender. Turning both of them off doesn't change anything.
5. I reset IE to defaults, including my personal settings (there weren't many as I've only been using this installation for about an hour and a half.) Again, no difference.

Thank you...I hadn't thought of the Safe Mode idea, and the other stuff I'd tried (but tried again). I don't know why, but the time thing, even though it's showing correctly, was something I focused on. But that still doesn't explain the missing dll's.

Samuria said:

What is your mtu set to Change your MTU under Vista, Windows 7 or Windows 8 richard-slater.co.uk can other pcs on the network get there ok?

That site is another that won't come up. (I get a blank page and a long attempt to connect judging by the activity spinner).

kyfho23 said:

That site is another that won't come up. (I get a blank page and a long attempt to connect judging by the activity spinner).

MTU is 1492

And the Richard-slater.co.uk eventually did come up.

What should it be test on the same site? set your dns to open dns same as 7 Use OpenDNS

Also, I tried pinging Google. 100% loss.

Samuria said:

What should it be test on the same site? set your dns to open dns same as 7 Use OpenDNS

OpenDNS is another site I can't get to, even to validate the DNS entries on the adapter page (Network and Sharing Center/Ethernet Status/Properties).

Try these fixes is it all browsers as it could be a certificate issue (Solved) Cannot Access Secure Sites - Https websites not opening View