Yahoo China has kicked up a storm after announcing that its email service will be deactivated from August 19, a move that is likely to affect about 5 million Chinese accounts.

Yahoo China said all email accounts and user content will be deleted after August 19. It did not explain the reason for its abrupt decision, irking its users.

Email users with suffixes .com.cn or .cn have been told to transfer all their archive material, content and addresses to a user account in Aliyun, Alibaba's search engine, or they will risk losing all their content.

After linking up with Aliyun, the Yahoo user ID will remain operational until the end of 2014.

Yahoo China subscribers can also hook up their accounts to other third party email service providers. Other Yahoo services, however, remain unchanged, the company said yesterday.

The sudden move has caught Yahoo China users by surprise, many of whom have been using the services for over 10 years.

The US company said in an email to Shanghai Daily yesterday that the decision was taken after consultations with its American headquarters. Yahoo China said the announcement was made to give its users sufficient time to make the jump elsewhere.

But that wasn't enough to assuage angry email users.

"I use this Yahoo email account for registration at many other websites and it is a lot of trouble to transfer and set up a new email account," said Lisa Lu, an office worker in her late 20s.

"There are so many files and contacts in my Yahoo mail. Isn't it irresponsible of such a big company like Yahoo to make this decision,?" wrote a microblogger with username Shia Li.

Hitwise, an Internet data service company, said the scrapping of Yahoo's mail service in China would affect about 2 percent of China's overall email users, or about 5 million accounts.

"I'm lucky to have transferred the majority of my emails from Yahoo China accounts a few years ago but now I'm worried what is going to happen if Microsoft or Google decide to close their email service as well," wrote another microblogger Unclewu.

According to a report by the China Internet Network Information Center released earlier this year, there has been a substantial drop in email users in China as netizens were increasingly favoring social networks and online video streaming sites that served multiple purposes as well.

Alibaba Group took over Yahoo China's business operation in 2005 after the US Internet giant invested US$1 billion to get a 46 percent stake in the Chinese e-commerce giant. But Alibaba's main focus has been its e-commerce operations that could have affected Yahoo China.