请在command窗口输入 sysdir 命令，把结果列出来。

我在plus文件夹中已经下载了很多命令，有可能与你想要下载的插件存在版本差异。
因此，如果是采用 ssc install 命令下载，一定要增加 replace 选项，如
ssc install xtbalance, replace

如果要采用 findit 查找，并根据弹出页面提示进行下载，则可能出现如下情况。
findit xtivreg2

--------------------------------------------------------------------------------------
package installation
--------------------------------------------------------------------------------------

package name:  xtivreg2.pkg
        from:  http://fmwww.bc.edu/RePEc/bocode/x/

checking xtivreg2 consistency and verifying not already installed...

the following files already exist and are different:
    D:\stata11\ado\plus\x\xtivreg2.ado
    D:\stata11\ado\plus\x\xtivreg2.hlp

no files installed or copied

Possible things to do:

    1.  Forget it
        (best choice if any of the above files were written by you and just
        happen to have the same name or you do not want the originals changed)

    2.  Look for an already-installed package of the same name
        (which you might then choose to uninstall)

    3.  Search installed packages for the duplicate file(s) by clicking
        on the file names above

    4.  Force installation replacing already-installed files
        (if this is an update, this would be a safe choice; you will end
        up with the original and the update apparently installed, but it
        doesn't matter; you can even uninstall the original later)

(no action taken)

r(602);

此时，你要选择第四种情况，强制安装，以便替换 plus 中的旧版本。

连老师，您好！
以下是我sysdir的内容，麻烦您帮我查看一下，谢谢！为什么有的在C盘，有的在D盘呢？我从来没有用D盘。

sysdir
   STATA:  C:\Thesis\stata11\
UPDATES:  C:\Thesis\stata11\ado\updates\
    BASE:  C:\Thesis\stata11\ado\base\
    SITE:  C:\Thesis\stata11\ado\site\
    PLUS:  D:\stata11\ado\plus\
PERSONAL:  D:\stata11\ado\personal\
OLDPLACE:  D:\stata11\ado\myado\







2# arlionn

老师，我把stata11改到d盘下就好了，呵呵，很简单的问题，感谢老师教我sysdir！

3# yellowriver

这个命令在stata初级2010版第二个视频文件中有详细介绍，你可以再好好看看。