ThankGOD I have two ISPs. One for broadband, the other for business email hosting.

All day yesterday and today up till 4pm, I could not access my business email using the usual bookmark; not could I even access their website from Google. <---VITAL POINT

Being the sort who does not give up easily, I found another way to contact them, and to my surprise on a bank holiday found them available for Live Chat, today. It went like this (some ID is xxx-d out): (saved chat)

You are now chatting with rubilyne
rubilyne: Good Afternoon
rubilyne: How can i help you today?
Me: Cannot access anywhere on silverserve.com all day yesterday and today <---stated right from the beginning
rubilyne: let me check
Me: So therefore I cannot check Boxtrapper, webmail etc.
rubilyne: im checking on it
rubilyne: can you try to access using this link xxxxxxxx.com/cPanel
Me: what would be the whole URL?
rubilyne: yes
Me: The server at www.silverserve.com is taking too long to respond.
rubilyne: or you can type www.xxxxxxxx.com/cPanel
Me: That yields:
Me: The requested URL /cPanel was not found on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
Apache/1.3.42 Server at www.xxxxxxxx.com Port 80

Me: The only bit which works is Talia.net, which is how I found this live chat.
Me: Nothing responds on silverserve.com on any computer here.

rubilyne: i have checked the other domains they are working fine
rubilyne: let me check your account
Me: It's not my account: emails are still coming in, thank goodness.
Me: This does nothing: https://www.silverserve.com/cpanel.php
rubilyne: no
Me: ??
rubilyne: it should be your domain name: / cpanel
rubilyne:www.xxxxxxxx.com/cpanel
rubilyne: let me check
Me: That is the bookmarked link which I have been using for years.
rubilyne: cause only your account is not working, i mean this link www.xxxxxxxx.com/cpanel,
Me: Years and years and years.
rubilyne: i see
rubilyne: it could be you need to update it <--- What? How?
Me: Also, trying to get into anywhere on silverserve.com from Google home: page, also does nothing all day yesterday and today. <----See this?
rubilyne: i understand with silverserve
rubilyne: im checking on it
rubilyne: you should access www.xxxxxxxx.com/cpanel
Me: Are you saying that some:thing has changed at silverserve.com and no-one has told me about it?
rubilyne: that is not what i meant
rubilyne: im saying that silverserve.com, im checking on it cause i cannot access to it as well <----GOOD CLUE HERE
rubilyne: instead using the silverserve, you can access the cpanel directly to this link www.xxxxxxxx.com/cpanel
Me: Nope. That does not work, as follows:
Me: Not Found
The requested URL /cPanel was not found on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
Apache/1.3.42 Server at www.xxxxxxxx.com Port 80

rubilyne: yes and it only happened to your domain
rubilyne: im checking on it
rubilyne: cause if you check this link www.anotherdomain.com/cpanel
rubilyne: it works fine
Me: But that is not much help to me:........
rubilyne: i know, what im trying to say its only your account
rubilyne: that's why i have to check further what is happening
Me: Thank you. I have done nothing at this end (of course). All I'm trying to do is access the usual page with boxtrapper and webmail. The same way as I've been doing it for years and years and years. Whatever is happening, it's not my fault!
rubilyne: yes, im not saying its your fault
Me: ok
rubilyne: that is why im checking what is happening exactly
Me: ok
rubilyne: and i do apologise for any inconvenience
Me: thank you
Me: Emails are still coming in thank goodness. It's a normal working day for us here; bank holidays are still working days.

Me: Look I've got to get on with work. Can you please email me: when you've found out what the problem is and what can be done. The email is xxxxxxxxxxxxxxxxxxxxxxx
rubilyne: yes, i will send you an update
Me: Could you also note that I cannot clear out Boxtrapper or anything else (on your servers) until I gain access?
Me: I've got to go.
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An hour later it worked exactly as it should. What had they done?

Rebooted the server. Doh!