Shoe wrote on 12/26/2015 11:58 AM:
I am having problems with file associations. I set an app to be used
with .pdf as an example. It eventually changes to Windows Edge with no
input from me. This has also happened with other file types, such as
.jpg. I then change it back and it may stay for some time before
changing again. I suspect this may be happening with Windows update,
but don't know for sure. Does anyone know how to lock these file
associations so they do not change?


I do not know of any way to "lock" these prefs. However, if it's just a
few file types you could export the registry keys and if it happens
again it's easy to use the registry files to reset the associations back
to where you want them.

Start - enter "regedit" (no quotes) - open HKEY_CLASSES_ROOT. Find the
desired file extension (e.g. .pdf), right-click, choose export, name the
file and save it where you like.

If the association later gets stolen just double-click that file and
merge it back into the registry. You need to log off, log on, or
restart for the change to be in effect.

--
Ed Mullen
http://edmullen.net/
After Tuesday the calendar says: "WTF"