Strange '403 Forbidden' Issue

[#1]

Hello again, all!

Although I'm no longer with PN, I know that the people here know an awful lot and may have at least a pointer for this problem I've having.

My set up is now as follows: BT Full Fibre through BT Hub 3 with wi-fi. My website is now hosted by Mystic Beasts (and thanks to those here who recommended them to me).

Here's the issue: from just over a week ago, I haven't been able to reach my own website on some browsers (things were OK for the first month or so after migrating the site).

On Windows 7, Firefox accesses just fine and shows a secure connection with a valid certificate from YR1, but Chrome and Vivaldi give me a '403 Forbidden' despite also showing that the connection is secure and cert is OK.

(On Android phone, I don't have Firefox installed, but Chrome and Vivaldi connect OK with the site both via mobile data and wi-fi through the Hub).

This is what I've done to try to diagnose the issue so far:

On the server side, I've tried toggling between 'Enable TLS' and 'Enable TLS with redirect to https:'. No difference.

(I can't see any issue with the .htaccess file; any problem with that would, I would guess, cause the same issue in Firefox).

On my own side, I've cleared cookies and site data in both Chrome and Vivaldi, and have tried Incognito mode in Chrome and Guest mode in Vivaldi. No change.

I've checked DNS on the Hub, which is set to 'Auto'. Again, I assume that this would have caused the same problem with Firefox if that was the issue.

I've cycled the power on the Hub (actually, that was done for me by a power cut after the problem became apparent).

I've toggled Windows Firewall on and off. Firewall settings on the Hub are set for UPnP and DMZ is off (I'm unable to set Access Control without downloading a blasted app!).

There's also a problem which may be adjacent to this one, in that links to my site from other sites which are coded without the 'www.' element in the URL cannot find the site ('Server Not Found').

I suspect that there's something amiss with the configuration of the site/server, but the hosting checklist at Mythical Beasts shows all is OK.

Before I get on to them, I thought that I'd run this past you all here just in case someone has any thoughts on what could be causing the issue.

Apologies for the length of this post, and thanks in advance for any suggestions you may have.

[#2]

Moderator's note:
Thread moved from Everything Else to Tech Help

[#3]

Ignoring the browser inconsistencies, HTTP 403 errors tend to point to something server side.

Links without the www prefix being broken sounds like a (domain) DNS issue. Do both www.yourdomain.tld and yourdomain.tld resolve in DNS?

From a Windows command line (replacing with your domain of course): -

> nslookup yourdomain.tld

[#4]

(Forgot to mention; I did flush the DNS cache as well)

This is what I get:

What's been throwing me about all this is that it isn't happening on all browsers and all platforms.

[#5]

@thejudge 

On Windows 7, Firefox accesses just fine and shows a secure connection with a valid certificate from YR1, but Chrome and Vivaldi give me a '403 Forbidden' despite also showing that the connection is secure and cert is OK.

(On Android phone, I don't have Firefox installed, but Chrome and Vivaldi connect OK with the site both via mobile data and wi-fi through the Hub).

Is it only Windows 7 that has the problem ? AI (which of course may well be wrong!) suggests

Google Chrome dropped support for Windows 7 long ago. An old version of Chrome cannot negotiate modern TLS handshakes with updated web servers, frequently resulting in connection or access rejections.

[#6]

---

@thejudge wrote:

(Forgot to mention; I did flush the DNS cache as well)

This is what I get:

What's been throwing me about all this is that it isn't happening on all browsers and all platforms.

---

This is missing the answer/reply for the second command. Did it succeed and return the same IP addresses as the first command?

@MisterW also raises a good point about Windows 7, what version of Chrome is installed on that machine? There's a chance it simply doesn't have the intermediate certificates/security cipher support that MB require for successful TLS negotiation. If you configure the site to allow connections over plain HTTP and that works, then it certainly points to something to do with HTTPS.

[#7]

@MisterW ,

The problems are on W7 with those two browsers.

The thing is, everything was OK until about 27/10, by which time I'd been at MB for over a month, and I didn't change anything at the time the problem started (to the best of my recollection).

For the record, I'm running Chrome v109.0.5414.120 and Vivaldi v5.6.2867.62

[#8]

@bobpullen 

What you see is what I got, Bob. Firstly with the 'www.' and then without it.

As I replied to @MisterW  a moment ago, I didn't have this issue until about a month after transferring the site to MB and made no changes that I can recall around the time the problem started.

I've now tried removing TLS altogether, and both Chrome and Vivaldi - after warning me that I don't have a secure connection - are coming up with the 403 as before, so I've re-instated TLS with redirect for now.

[#9]

@thejudge 

For the record, I'm running Chrome v109.0.5414.120

well that's a VERY old version of Chrome , I dont currently have Chrome on my Windows machine but AI says the latest Windows version is 158.0.8127.18 (or .19) 

The thing is, everything was OK until about 27/10, by which time I'd been at MB for over a month, and I didn't change anything at the time the problem started (to the best of my recollection).

You might not have changed anything but MB may well have done on the shared hosting platform.

Any chance you can test with an up to date Windows and Chrome version ?