Router won't load https/ secure pages? Help please!

[Holstein]

Exactly that- DS broke the old router (indoor cricket, ahem) so we bought a new one- Netgear, so a decent, well-known brand.
It seems to work okay, apart from this one issue, whereby https pages won't load. Some will (e.g. Halifax Bank) others won't (e.g. Amazon basket, NatWest, John Lewis basket etc) .
It's a Netgear D3600 if that helps.
Any ideas please? (other than turn it off and on again, which I've tried )
TIA

Have you tried checking your firewall settings which may be restricting access or installed any new software?
Has your router been provided by your internet provider? If not, is it definitely compatible with your network providers parameters?

Just a couple of suggestions from my DH who is shouting suggestions from the showere!

Shower!

Or try doing a router reset by pressing the reset button on the back of the router for 20 seconds.

DH says all machines on the network are affected, not all the machines have local firewalls (e.g. phones, chromebook etc). The router doesn't have a firewall, it provides some DOS protection, which he's disabled, but made no difference.
He checked it works with our provider. He is reluctant to do a router re-set, as he'd have to back-up the settings and re-apply them ().
All traffic to port 80 works. Traffic to port 443 works for some domains, but not others (consistently). EG google.com works with https.

Dunno if any of this helps.

It had quick-configure mode which included our provider in a pull-down list.
That auto-detected the settings, and he checked them against the published settings from our provider and they matched.

Thanks, btw!

Were you given the option to buy your router from your broadband provider? It's just they can carry out diagnostic tests from their end.

I don't think we even thought we could, tbh!

Do you think it's worth ruining their helpline then? I assumed people on here would know more than they would

DH said we did have one, but it was v low quality, and the wifi was inadequate. It didn't communicate well with the linux devices.

Lots of people don't like to buy their routers from their providers as they tend to be more expensive unless there's an offer on. We had a problem with ours, I am not technologically minded at all but rang Sky, our provider, who were excellent. They took me through some trouble shooting which did the trick. You could try ringing your provider but they probably won't be able to help unless it's one of their routers.
Good luck!

Thanks

Have you checked the blocking page

1.Launch an Internet browser from a computer or WiFi device that is connected to thenetwork.

2.Type www.routerlogin.net.A login screen displays.

3.Enter the user name and password for the modem router.The user name is admin. The default password is password. The user name andpassword are case-sensitive.

4.Click the OK button.The BASIC Home screen displays.

5.Select ADVANCED > Security > Block Sites

See if any sites are keyword blocked.

The router can't tell the difference between http and https they are handled by the browser

Thanks, we checked that.

Argh, so we reset it, and now the admin console won't come up. Must be faulty.