[Deceive]

See, for example I've installed MyBB forums at my site hello.com
I've a page which shows 'Checking your browser stuff' let's name it checking.com (It's an HTML file).

So, what I want is I whenever a guy accesses hello.com, he first gets showed up with checking.com stuff and then back to hello.com in 5 seconds but the issue is I've already installed every stuff on hello.com and can't remove them.

Any help?

[Bish0pQ]

Shoot me a PM with more information and I might be able to help you.

[Wildfire]

A few things:

Checking.html MUST BE CACHED. Otherwise you're not helping anyone mitigate anything.
Checking.html MUST DO MATHEMATICAL BROWSER CHECKS.
I recommend using a cookie that is checked serverside and dictates whether or not to force-301 the user.

[Deceive]

Well I'm all new and totally know nothing much, so it'd very kind if you elaborate.

[sleaze]

attempting your own mitigation is usually a bad idea, just saying