Galaxy 5 phone won't open programs from 'My Files' app

[+findertwo]

This is my first attempt at a Wherigo cache. I'm using a Samsung Galaxy 5 phone and the app program WhereYouGo app from the Play Store. I'm also running from Geocaching.com direct as opposed to from the app.

 

After all the logins, I managed to download two programs from the WERIGO website for cache 'Getting to Know Waterford Oaks. GC52PA9'. Those programs are: 1)Getting To Know WA.GWC and 2)PlayInstall.CAB

 

When I pick either file I get 'OPEN FILE' at the top of the Galaxy 5 screen and then this message in the middle of the screen: 'ALL APPS ASSOCIATED WITH THIS ACTION HAVE BEEN TURNED OFF, BLOCKED, OR ARE NOT INSTALLED.'

 

I am totally lost.

 

Any help would be most appreciated as I'm really anxious to start a Wherigo adventure and I don't have a lot of phone technical savy.