Disassociating file extension program

All that accomplished was letting me see that there were two possibilities for Open with BLORT is not listed there but is now the default. I'd love to see the Use-case analysis that allowed this scenario and still managed to not allow anything useful.

I didn't complete the suggested steps. HAR file I do get the How do you want to open this file? I guess that's the answer. How can I remove extension association in Windows 10? What file extension are you referring to? If you run assoc with no arguments does it actually show a current association? I really don't care about the points, marking it as an answer may help someone else with the same problem.

How about remove the related. Please remember to mark the replies as answers if they help, and unmark the answers if they provide no help. If you have feedback for TechNet Support, contact tnmff microsoft.

I agree with the other comments about assoc but think you should also check under Default Programs because it seems that there is now a lot of stuff in there which does not get reported by either assoc or ftype.

Also, note that the Set Associations list is a 2 part list and it is not searchable; so you must scroll through it to find the top and bottom of all its ranges.

I have already listed all the registry by find function for this extension before I posted this question but the association as I know it from the past or from other extensions, I haven't found.

BTW "extension abbreviations" are often not included in File Type names, so no surprise that you might not see yours listed there. That's a great example of how horribly unusable these new undocumented "discoverable" UX can be. The UI suggests that it would let me disassociate it from Notepad provided that the Store knew about it. Well, evidently the Store doesn't know about it and there is no obvious way to switch it from an association with Notepad to Unknown.

Unknown appears to be the association that represents files with extensions that exist but are not associated with a program. There is nothing in the UI which allows us to either associate an extension with that Unknown class or delete one. I remember now making observations about these deficiencies before during a preview.

So, for a workaround for this deficiency it looks like my only hope would be to create something using another method, hope that that collides with whatever the GUI is using, then delete it with a non-GUI method and hope that that produces an Unknown association in the GUI? Or just hack the registry as some have already suggested.

I need to find a better example. HAR matches common words such as Hardware and Share so it won't be practical to try to find all the implementation details in the registry for it. And I have one! It looks like it was created by IE Developer Tools. I probably used Notepad to inspect it and didn't notice that I was creating an association and filetype at the same time.

Maybe deleting it or renaming its extension will change that association. Who knows? All you have to do is right click, select Open with and choose the program you want to open it. Here we show you some ways to remove file extension associations in Windows.

Types is quite an easy program to use and it has one major advantage over the other third party tools here. The others will be able to delete more basic associations or delete all associations in Windows 7. If you have issues with your file extension not clearing itself in Windows 10, try this. Types can both delete the extension or just remove the file type association. Click the Delete button or press Del on the keyboard. To do that, instead of pressing Delete, select Properties or double-click.

Uncheck the Class box to remove the file type from the extension. There are portable, command line, and installer versions of Types available, portable and CLI are at the bottom of the webpage in small text. The installer can add an entry into Control Panel for easy access. Windows 10 users will need. NET Framework 3. Download Types. Multiple removals at once are possible with the use of Ctrl and Shift.

Then press the Detach File Type button at the bottom. If the extension is still associated, you might have previously set it to manually open with another program. Please remember to be considerate of other members.

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