Windows 10: I just noticed that Windows 10 changed the default app for the .ost file type to Adobe...

I just noticed that Windows 10 changed the default app for the .ost file type to Adobe Acrobat with the red Adobe logo. See attached screenshot: I tried to change it to Outlook, but, in the settings page for default apps, Windows did not show that Outlook was a choice--and, worse, when I searched in the AppStore as suggested by Windows, Outlook did not show up as a choice. Instead, all choices for .ost apps in the AppStore looked like third-party PDF apps or third-party OST-management apps. Can you suggest a solution? /s/ Jim D.

:)

 

Changing the File Type on an Outlook *.OST file.

I did a stupid thing and inadvertently changed the file type of an Outlook 2016 OST file to a PDF file. I have tried to change the type of file that *.OST is used by to Outlook but Windows 10 does not let me. Does anyone have any suggestions.

Thanks

 

How to change default app for file type

'Open With > Choose another app' has three step, in the first it only offers apps registered for that file type. If you click 'More apps' it lists all registered apps regardless of suitability. Both these steps have the tick-box for 'Always use...' in my 18363.752. The third step, if needed, is 'Look for another app on this PC'. The 'Always use...' must be ticked before taking this step if you want the change to stick. However, WMP appears at the second step.

For a quick look at a JPG almost anything (including WMP) is more practical than Photos which on my system takes more than ten seconds just to open a photo. The OP is probably not aware that the Windows Photo Viewer is still available in W10, but hidden away. That's my default viewer for JPG.


Restore Windows Photo Viewer in Windows 10

And, once enabled, is available in Settings > Apps > Default apps.

 

How to change default app for file type

@Bree - yes, I'm quite aware of this thanks, but as you will see it's missing. I recall reading that clicking the dialogue at a certain point in blank space made it appear, and trying that once successfully, but doesn't seem to help now. Plenty of other similar reports of this option being missing.





'Fix' described here: (essentially unassociate the extension)
Windows 10 "Always use this app" checkbox missing - Super User