每次打开百度或发送邮件等其他操作时，打不开我要进入的下一个网页，会出现这样一个界面，内容如下：
Insecure Internet activity. Threat of virus attack
Due to insecure Internet browsing your PC can easily get infected with viruses, worms and trojans without your knowledge, and that can lead to system slowdown, freezes and crashes.
Also insecure Internet activity can result in revealing your personal information.
To get full advanced real-time protection for PC and Internet activity, register KvmSecure.
We recommend you to protect your PC now and continue safe Internet browsing.
Click here to get full advanced real-time protection and continue browsing.
Continue to this website unprotected (not recommended).
我想问：
一、是怎么造成这种情况的？
二、如何解决（方法要详细）
三、以后如何预防
请各位高手在百忙中赐教，不胜感谢！
我不是让你们翻译，是寻求解决放法
再者我的电脑是办公室工作用的，里面有很多软件，不能重做系统。否则软件没了没法装。那些软件是统一装得，网上就没有下载得