Experts HowToGeek and Bleeping Computer have drawn attention to a strange bug, which sometimes manifests itself in Windows 10 users and makes it difficult to assign programs by default.
Apparently, the problem arose after the April update was released for Windows 10. Although it was assumed that the October 1809 build release was correct, Reddit users still complain about the problem and it appears that this patch has not helped everyone.
Here it should be noted that the essence of the problem is not yet clear until the end, and not all users have the bug. The fact is that sometimes Windows 10 simply does not allow the user to modify the default program to open a particular type of file. For example, the operating system does not allow you to associate the .txt file with Notepad ++, while for this you can freely assign any other application.
Dissatisfied researchers and users write that they have not yet succeeded in identifying at least some coherence and logic in what is happening. Windows 10 may refuse to assign Adobe Photoshop for images or Notepad ++ for text files as default applications, but at the same time it may allow IrfanView, VLC or Google Chrome to become default applications. The problem in action can be seen in the underlying animation.
Apparently, the error concerns only certain programs, certain users and manifests itself under a certain set of circumstances (which, it is not yet clear).
The journalists of Bleeping Computer note that in recent months the problem has been repeatedly reported to Microsoft engineers (through the Feedback hub for Windows Insider build). Below you can see one of these reports.
Unfortunately, it seems that at the moment there is not a solution to this problem. Microsoft representatives have not yet responded to media requests.