原因是没有选择“以管理员身份运行”。具体选择该按钮的方法如下(以windows10系统的chrome浏览器为例):
1、打开浏览器,在百度搜索栏中输入“QQ”,并回车。
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2、在接着打开的页面中点击第一个搜索结果并进入官网。
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3、点击“立即下载”,将QQ下载到电脑桌面上。
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4、右击QQ安装程序图标,在随后打开的下拉菜单中点击“以管理员身份运行”按钮,即可正常安装QQ。
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