出现此报错主要是由于您的一项系统文件丢失导致。请您访问以下链接，下载fp4autl.dll文件，保存于桌面，如果下载后文件没有后缀名，请将其重命名为fp4autl.dll。

然后将此文件存放于以下位置：C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\40\Bin

完成之后，请您再次尝试安装Office 2010，看看此时能否安装成功。
方法二：

When trying to install Office 2010 on a machine with XP sp3 that currently runs Office 2003 I get the following message.

"Microsoft Office Professional Plus 2010 encountered and error during set up.

The Windows Installer cannot update one or more protected windows files."

Any help please?

This may have happened because in optimizing Windows XP down, some files were deleted.

You can follow these steps resolve this problem:

1.  From Windows install disk go to E:\I386 folder and open (Double click) on the FP40EXT.CABcompressed ile. 
(or - if you do not have the disk, find a working XP computer and go to C:\Program Files\Common Files\Microsoft Shared\web server extensions\40\bin).

2.  Find fp4autl.dll in the list and copy it (ctrl-c).

3.  Go to c:\program files\common files\microsoft shared\web server extensions\40\bin and paste it (ctrl-v).

4.  Restart Office 2010 install.

Note: Please do NOT download fp4autl.dll from Internet.