According to reports in local media, the cooperation between the Chinese security software providers Qihoo 360 and Kingsoft has come to an abrupt end.

The cooperation, which is reportedly the first partnership in China's security software industry during the past ten years, started from July 2009 when the two parties jointly launched customized security services on each other's platforms. However, it ends in a war of words caused by the compatibility problem between 360's security browser and Kingsoft's network shield product.

Prior to this, users in China complained about the compatibility of 360's security browser and Kingsoft's network shield anti-virus software. In response to the complaints, Kingsoft said 360's new edition browser was intentionally preventing users' normal use of the network shield; while 360 said the problem was caused by technical defects in Kingsoft's product.

The argument was eventually raised to the revenue model of security software. The accusations from executives at 360 were that Kingsoft is retaliating against 360's free-to-use policy; while Kingsoft stated its network shield can turn 14 browsers into security browsers and there is no reason for users to use 360's security browser.

At present, 360 has suspended the download service of Kingsoft Duba software on its website and the promotion for Kingsoft Duba has also been removed from 360's security software.