Win7下面的無後綴文件默認是無法設置默認打開程序的，每次打開都得選擇程序去打開，很是麻煩，而且根本百度不到解決方案。
那麼，我們可以嘗試強制修改註冊表來搞定它。
正常情況，在註冊表HKEY_CLASSES_ROOT下面能看到各種類型文件&後綴，但是沒有 “.”,也就是說Win7沒有爲無後綴文件設置默認程序。我們要做的就是要建立一個“.”.
你不用自己建立了，挺麻煩，直接導入我做好的的註冊表文件吧（看文章最後，那就是註冊表文件）。導入完成後，你就能看到這個“.”了。還不能用，你需要在./shell/open（print, printto可選)/command/下面重新把你喜歡用的默認文本編輯器替換過來，我自己的路徑你們不一定可用。
然後在任務管理器中關閉iexplore.exe的進程，再重建一次，這樣新的註冊表就生效了，現在去打開你們的無後綴名文本文件試試吧！
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隨便新建一個空白註冊表文件test.reg，然後文本編輯器打開，把下面內容複製進去：
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\.]
"DefaultIcon"=hex(2):00,00
"EditFlags"=dword:00010000
@="Text Document"
"FriendlyTypeName"=hex(2):40,00,25,00,53,00,79,00,73,00,74,00,65,00,6d,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,00,6e,00,6f,00,74,00,65,00,70,00,61,00,64,00,2e,00,65,00,78,00,65,\
00,2c,00,2d,00,34,00,36,00,39,00,00,00
[HKEY_CLASSES_ROOT\.\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,00,73,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,69,00,6d,00,\
61,00,67,00,65,00,72,00,65,00,73,00,2e,00,64,00,6c,00,6c,00,2c,00,2d,00,31,\
00,30,00,32,00,00,00
[HKEY_CLASSES_ROOT\.\shell]
[HKEY_CLASSES_ROOT\.\shell\open]
[HKEY_CLASSES_ROOT\.\shell\open\command]
@=hex(2):44,00,3a,00,5c,00,50,00,72,00,6f,00,67,00,72,00,61,00,6d,00,20,00,46,\
00,69,00,6c,00,65,00,73,00,20,00,28,00,78,00,38,00,36,00,29,00,5c,00,4e,00,\
6f,00,74,00,65,00,70,00,61,00,64,00,2b,00,2b,00,5c,00,6e,00,6f,00,74,00,65,\
00,70,00,61,00,64,00,2b,00,2b,00,2e,00,65,00,78,00,65,00,20,00,25,00,31,00,\
00,00
[HKEY_CLASSES_ROOT\.\shell\print]
[HKEY_CLASSES_ROOT\.\shell\print\command]
@=hex(2):44,00,3a,00,5c,00,50,00,72,00,6f,00,67,00,72,00,61,00,6d,00,20,00,46,\
00,69,00,6c,00,65,00,73,00,20,00,28,00,78,00,38,00,36,00,29,00,5c,00,4e,00,\
6f,00,74,00,65,00,70,00,61,00,64,00,2b,00,2b,00,5c,00,6e,00,6f,00,74,00,65,\
00,70,00,61,00,64,00,2b,00,2b,00,2e,00,65,00,78,00,65,00,20,00,2f,00,70,00,\
20,00,25,00,31,00,00,00
[HKEY_CLASSES_ROOT\.\shell\printto]
[HKEY_CLASSES_ROOT\.\shell\printto\command]
@=hex(2):44,00,3a,00,5c,00,50,00,72,00,6f,00,67,00,72,00,61,00,6d,00,20,00,46,\
00,69,00,6c,00,65,00,73,00,20,00,28,00,78,00,38,00,36,00,29,00,5c,00,4e,00,\
6f,00,74,00,65,00,70,00,61,00,64,00,2b,00,2b,00,5c,00,6e,00,6f,00,74,00,65,\
00,70,00,61,00,64,00,2b,00,2b,00,2e,00,65,00,78,00,65,00,20,00,2f,00,70,00,\
74,00,20,00,22,00,25,00,31,00,22,00,20,00,22,00,25,00,32,00,22,00,20,00,22,\
00,25,00,33,00,22,00,20,00,22,00,25,00,34,00,22,00,00,00