You just have to be patient and check later.
Due to a virus in the server, the web site was temporarily unavailable.
You just have to wait until they fix it. It probably won't take so much time.
You should wait for a few hours then.
Nothing, you just have to wait.
They used to, the site is temporarily unavailable for maintenance so I can't double check. I'm pretty sure they do not anymore. I think you have to by it online. Google it.
Clear your browser cache
There are a few reasons. It is usually available though. They block there site from certain countries. Schools block youtube, as do public web access areas.
If a website is unavailable you cannot access current messages.
this is due to site maintenence..
Highly improbable - they're more likely to suspend your access to their site (either temporarily or permanent).
cameras on Earth Cam may go temporarily unavailable due to satellites being blocked for short periods of time as the Earth moves in space.
no