Set Default App

[Eagle710]

How would I set the default application for a certain extension using Registry. Im trying to this the tricy way obviously but thats how I learn and work best. So i have .pdf and I want it to open using SumatraPDFPortable.exe ......any ideas?

[gosh]

the easiest is just go to filetypes in folder options and change the default action

or in regedit go to HKCR\<extension> and change it there directly