Fix Open with “Choose another app” Error Program Not Associated in Windows 10

When you right-click a file, and select Open with… in a Windows 10 computer, the following error may appear:

This file does not have a program associated with it for performing this action. Please install a program or, if one is already installed, create an association in the Default Programs control panel.

Or if the Open with… menu expands and you click the Choose another app option in the submenu, the same error may be seen.

This happens if the following registry, its sub keys or some of its values are missing:

HKEY_CLASSES_ROOT\Unknown

To fix the problem, download w10_unknown.zip, unzip and run the enclosed REG file w10_unknown.reg.

Note: This REG file is to be used in Windows 10 systems only. For a Windows XP, Vista and 7 version of this fix, check out this page.

Here is the contents of the REG file:

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\InvokeDefaultVerbInOtherProcess]
"ProgrammaticAccessOnly"=""

[HKEY_CLASSES_ROOT\Unknown\shell\InvokeDefaultVerbInOtherProcess\command]
"DelegateExecute"="{e44e9428-bdbc-4987-a099-40dc8fd255e7}"

[HKEY_CLASSES_ROOT\Unknown\shell\Open]
"MultiSelectModel"="Single"
"ProgrammaticAccessOnly"=""

[HKEY_CLASSES_ROOT\Unknown\shell\Open\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,00,4f,00,70,00,\
65,00,6e,00,57,00,69,00,74,00,68,00,2e,00,65,00,78,00,65,00,20,00,22,00,25,\
00,31,00,22,00,00,00
"DelegateExecute"="{e44e9428-bdbc-4987-a099-40dc8fd255e7}"

[HKEY_CLASSES_ROOT\Unknown\shell\openas]
"MultiSelectModel"="Single"
@=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,00,73,00,\
68,00,65,00,6c,00,6c,00,33,00,32,00,2e,00,64,00,6c,00,6c,00,2c,00,2d,00,35,\
00,33,00,37,00,36,00,00,00

[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,00,4f,00,70,00,\
65,00,6e,00,57,00,69,00,74,00,68,00,2e,00,65,00,78,00,65,00,20,00,22,00,25,\
00,31,00,22,00,00,00
"DelegateExecute"="{e44e9428-bdbc-4987-a099-40dc8fd255e7}"

[HKEY_CLASSES_ROOT\Unknown\shell\OpenWithSetDefaultOn]
"MultiSelectModel"="Single"
"ProgrammaticAccessOnly"=""

[HKEY_CLASSES_ROOT\Unknown\shell\OpenWithSetDefaultOn\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,00,4f,00,70,00,\
65,00,6e,00,57,00,69,00,74,00,68,00,2e,00,65,00,78,00,65,00,20,00,2d,00,6f,\
00,76,00,65,00,72,00,72,00,69,00,64,00,65,00,20,00,22,00,25,00,31,00,22,00,\
00,00
"DelegateExecute"="{e44e9428-bdbc-4987-a099-40dc8fd255e7}"

About the author

Ramesh Srinivasan founded Winhelponline.com back in 2005. He is passionate about Microsoft technologies and he has been a Microsoft Most Valuable Professional (MVP) for 10 consecutive years from 2003 to 2012.

4 thoughts on “Fix Open with “Choose another app” Error Program Not Associated in Windows 10”

  1. Thanks a ton. I had been looking for a solution and nothing worked. then tried googling invokedefaultsverbinprocess and it worked!

  2. Man! Thanks a lot! I was looking for solutions to my problem with the “choose another app”. Glad i trusted you bro great job! 🙂

  3. thanks a million! i tried several other methods to no avail but this worked. i presume ccleaner’s registry cleaner did this to me but not 100% sure…

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