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。
将以下代码另存为*.reg，双击运行导入
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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
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