"Request forbidden by administrative rules" when trying to access Admin panel

[Sono]

I get this error page when I am trying to access the Admin panel of my forum:
"403 Forbidden
Request forbidden by administrative rules."

Me and my friend is the admin of the forum, he did not change anything in the admin panel as he said. I can moderate, delete posts, make posts, etc., but I am unable to reach the admin panel. From the Member list, I can see there are no more andmins besides us. Only the two of us. What might have happened? Forum hacked? Any chance to reset my account to be able to reach the admin section? How to check if hacked?

[Aleksi "Lex" Kilpinen]

Seems like the url triggers a security rule that your host has enforced, contact your host.

[Sono]

I have just tried to log in and access the admin panel from a freshly installed Opera browser (I have had Chrome and Firefox so far) with all history emptied from it, and in that one it works. I can access everything. So what is happening here actually?

[Aleksi "Lex" Kilpinen]

Not sure, a 403 is a server side error - If you have access to your server's error logs, they might be able to shed some light on this.

[Shades.]

Sorry I can't be of help here but...

I have this same problem trying to reach the WebDev site with any browser other than Opera VPN.

[Sono]

Not sure, a 403 is a server side error - If you have access to your server's error logs, they might be able to shed some light on this.

You mean this kind of error?

"Temporary network issues on Shared hosting servers
We would like to inform you that we are currently having temporary network issues on our Shared hosting servers. As a result, the /admin page of the websites hosted on our servers may be inaccessible. More details can be found here.

We will get back to you as soon as possible. Thank you for your understanding and cooperation."

Good to know at least what this error might mean. Have not ever met this one.

[Aleksi "Lex" Kilpinen]

To be perfectly honest I think that message is a bit vague and perhaps even intentionally so - but yes, that might very well be related.

A 404 means server received your request but has no content to show in response,
a 403 means server received your request but is not allowed to show you the content it has.
Both are server errors, which should usually mean it isn't a network issue (unless the network is redirecting traffic to a wrong server).

EDIT:
If it's Namecheap - Then yeah, the more detailed information includes some further explanation, which doesn't look very reassuring.
They have blocked admin interfaces to lower server loads across the board - which really sounds bad IMHO.