安装Visual Studio 2005,2008都三年了，从来都没遇到过什么问题，安装过程都很顺利。今天给公司的新电脑装系统，自带了一个正版的Win XP家庭版，安装VS的时候出错，1330错误：某个文件数字签名不可用。于是换了张光盘，结果还是同样的结果。。。于是换系统，先装Win2003，最 后到Win2008，都逃不过这个问题，而且数字签名不可用的文件每次都是随机的，有时是第2个文件，有时是第60个文件。找来师哥们帮忙，他们也没遇到 过这么怪的问题。后来在Google上搜索"Visual Studio 1330"，找了很久，微软MSDN版主的解释是文件损坏，重新下载安装。（PS：公司里的Visual Studio光盘是MSDN寄来的光盘，有20多张DVD，包括所有语言的版本）。还有的是让把光盘里的文件复制到硬盘安装。。。。测试无效。

Finally,通过Google在一个老外的博客上找到了解决方法：在注册表中，把原HKCU\Software\Microsoft\Windows \CurrentVersion\WinTrust\Trust
Providers\Software Publishing\State 的值由 0x23c00 改为 0x22800。关闭文件数字签名验证。VS顺利安装！

下面附原博客内容：

FIX: Error 1330 - Installing Visual Studio 2008 on Windows Server 2008 VPC
OK, I have run into SO many bloody 1330 errors while installing Visual Studio 2008 on a Windows Server 2008 VPC. Here is the fix I ran across on Heath Stewart's blog.

On my host, I installed the Windows SDK for Windows Server 2008 and .NET Framework 3.5.

I then copied SetReg to my VPC image from my host's C:\Program Files\Microsoft SDKs\Windows\v6.1\Bin.

I then updated my SetReg settings on the VPC as is mentioned in Heath's article.

Software Publishing State Key Values (0x22800):
   1) Trust the Test Root........................... FALSE
   2) Use expiration date on certificates........... TRUE
   3) Check the revocation list..................... TRUE
   4) Offline revocation server OK (Individual)..... FALSE
   5) Offline revocation server OK (Commercial)..... TRUE
   6) Java offline revocation server OK (Individual) FALSE
   7) Java offline revocation server OK (Commercial) TRUE
   8) Invalidate version 1 signed objects........... FALSE
   9) Check the revocation list on Time Stamp Signer FALSE
10) Only trust items found in the Trust DB........ FALSE

Reran the VS2008 install and PRESTO! it worked w/ no Error 1330s.

FWIW, I am writing this down here on my blog so I have it semi-permanently for future such mishaps. :-)