最近不知道为什么在win7下用ie9下载文件后虽然文件已经下载到硬盘了，但是不能直接在工具条的“open”按钮打开，也不能打开“view downloads”，搜索解决方法发现很多人对这个问题答非所问，找了很久，在一个英文页面上找到了解决方法，感觉应该是downloads文件夹里下载的东西太多了，然后不知道什么原因造成了前述两个按钮失效，不知道以后经常清理downloads文件夹会不会好一些。

下面是问题的具体解决方法：

You may have a corrupted Download History list. You can fix this by simply clearing the list using the built in functionality listed below:
 •Open Internet Explorer
•Press Ctrl + Shift + Del on your keyboard
•Uncheck all of the boxes that are displayed in this window
•Check the Download History box
•Click Delete
•Close the Internet Explorer window
•Wait for the deletion process to finish
•Open Internet Explorer
 
Then test to see if you now have a normally functioning Download History window.