Reports from China state that Google e-mail has been blocked by the country's censors. Known unofficially as the Great Firewall, governmental censorship is said to have blocked access to Gmail, through Virtual Private Networks (VPN), which are workarounds for many Chinese users seeking to evade restrictions on the Internet.
I know that many compliance officers, including this writer, routinely use Google e-mail when dealing with resources overseas that are supplying information for due diligence investigations, due to the level of encryption Google uses, and the ease with which images and attachments are used.
Be advised that the reason for the inability of Chinese sources to communicate with them in this manner is the new blocking of access. You will need to reestablish communication links through an alternate route.