Dropbox, the easiest online backup and synchronization tool, is facing a serious issue. According to the reports reported by few users, the Dropbox website and the desktop client are not working in China.
After this ban, Dropbox is the latest victim of the great firewall of China. Many big websites including Twitter and Facebook are already inaccessible in the country.

Many Dropbox users have reported (using proxy websites and tor) this issue in the official Dropbox forum. User TianYi commented:
1 hour ago, dropbox was blocked by China Greate Fire Wall:
http://en.wikipedia.org/wiki/Golden_Shield_Projectincluding homepage, forum, votebox and all urls that contain "dropbox.com", but dropbox client runs well.
Now I’m posting my words through tor network, but it will be very slow when syncing files, if China gov block the client.However, that’s also a good news, well, because facebook, twitter, google and some great companies are also blocked or partly blocked in China, now dropbox joins this group. That’s an honor.
Farewell, dropbox.
Another user, Rasmus Dah, reports:
The client does NOT run well – actually not at all in south China.
Though, the Dropbox has not officially confirmed this issue so far.
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yes .. it is NOT working in at least few areas of country. see this report
link
Actually, if you run Vidalia and set up Dropbox to use the proxy, it does run. I know, I’ve used it in China, but I prefer to remain anonymous.
DropBox is great and it gives 2 GB of online storage for your computers that you can easily use to transfer files between multiple computers, iPhones, iPod Touches, and iPads for free.