I am not sure is this is the right category; however, my client has suddenly started receiving the following message when trying to access her CMS site
This site can’t provide a secure connection
1drv.ms uses an unsupported protocol.
ERR_SSL_VERSION_OR_CIPHER_MISMATCH
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Unsupported protocol
The client and server don’t support a common SSL protocol version or cipher suite.
and
Can’t connect securely to this page
This might be because the site uses outdated or unsafe TLS security settings. If this keeps happening, try contacting the website’s owner
1dtv.ms is the Microsoft OneDrive share URL that use used when you share links via Onedrive. This obviously is not the URL of your site. You might want to have the user provide more info or …
Confirm the correct URL is loaded in the browser, identify the the OS, browser, and browser version. Have the user visit the site in Incognito mode with NO browser extensions to see if the same occurs. Check the DNS settings if a redirect is happening. If DNS is poisoned then recommend using 1.1.1.1 Cloudflare DNS → https://1.1.1.1 for primary DNS if possible (I would use it anyway).
I agree a client issue - which I still have to solve. I use Webflow hosting and it looks ok - what do you mean by poisoned? It looks OK when I check it?
The reference means a non authoritative IP address is returned by the DNS query, which is made against a non authoritative DNS server. This can happen on compromised machines. Not saying that is the case, but it is a possibility.
If the client visits the site, they should be able to inspect the certificate. It should show the data I posted. If it does not, then a game is afoot.