这是今天配置电脑PHP和MySQL的时候无意间发现的，不知道是什么时候开始出现的问题。

问题描述：

Windows 7打开方式选择默认程序或者打开未知格式文件的时候出错：该文件没有与之关联的程序来执行该操作。请安装一个程序，或者，如果已安装程序，请在“默认程序”控制面板中创建关联。通过百度、谷歌搜索多种解决方法没有解决，使用优化软件修复没有效果，具体产生错误原因未知，不过最终还是找到了解决方法。

解决步骤具体如下：

1、新建记事本文件，将以下代码复制粘贴进去;

Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\Unknown]
“AlwaysShowExt”=””
“QueryClassStore”=””
“TypeOverlay”=””

[HKEY_CLASSES_ROOT\Unknown\DefaultIcon]
@=hex(2):25,00,53,00,79,00,73,00,74,00,65,00,6d,00,52,00,6f,00,6f,00,74,00,25,\
00,5c,00,53,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,73,00,68,00,\
65,00,6c,00,6c,00,33,00,32,00,2e,00,64,00,6c,00,6c,00,2c,00,30,00,00,00

[HKEY_CLASSES_ROOT\Unknown\shell]
@=”openas”

[HKEY_CLASSES_ROOT\Unknown\shell\openas]
“MultiSelectModel”=”Single”

[HKEY_CLASSES_ROOT\Unknown\shell\openas\command]
@=hex(2):25,00,53,00,79,00,73,00,74,00,65,00,6d,00,52,00,6f,00,6f,00,74,00,25,\
00,5c,00,73,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,72,00,75,00,\
6e,00,64,00,6c,00,6c,00,33,00,32,00,2e,00,65,00,78,00,65,00,20,00,25,00,53,\
00,79,00,73,00,74,00,65,00,6d,00,52,00,6f,00,6f,00,74,00,25,00,5c,00,73,00,\
79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,73,00,68,00,65,00,6c,00,6c,\
00,33,00,32,00,2e,00,64,00,6c,00,6c,00,2c,00,4f,00,70,00,65,00,6e,00,41,00,\
73,00,5f,00,52,00,75,00,6e,00,44,00,4c,00,4c,00,20,00,25,00,31,00,00,00
“DelegateExecute”=”{e44e9428-bdbc-4987-a099-40dc8fd255e7}”

[HKEY_CLASSES_ROOT\Unknown\shell\opendlg]
“LegacyDisable”=””
“MultiSelectModel”=”Single”

[HKEY_CLASSES_ROOT\Unknown\shell\opendlg\command]
@=hex(2):25,00,53,00,79,00,73,00,74,00,65,00,6d,00,52,00,6f,00,6f,00,74,00,25,\
00,5c,00,73,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,72,00,75,00,\
6e,00,64,00,6c,00,6c,00,33,00,32,00,2e,00,65,00,78,00,65,00,20,00,25,00,53,\
00,79,00,73,00,74,00,65,00,6d,00,52,00,6f,00,6f,00,74,00,25,00,5c,00,73,00,\
79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,73,00,68,00,65,00,6c,00,6c,\
00,33,00,32,00,2e,00,64,00,6c,00,6c,00,2c,00,4f,00,70,00,65,00,6e,00,41,00,\
73,00,5f,00,52,00,75,00,6e,00,44,00,4c,00,4c,00,20,00,25,00,31,00,00,00

这是网上某高手给出的解决方案，暂时未发现副作用，仔细分析导入项，很容易发现，只是一些简单的注册表项出错导致的错误。

2、将以上代码另存为*.reg，双击运行导入，如果杀毒软件阻止只管允许即可;

3、如果对.reg文件建立不是很清楚可以下载源文件直接导入;有需要可以点此下载Open-With-Error.