Just ignore that message, all that says is you have already downloaded it once.
Just click on INSTALL and do it again, I have redownloaded 100s of apps over and over again.
Or, on the phone itself, open Goggle Play store, and then "My Apps".
It will search thru your phone and only show the apps that you currently have on the phone.
Then search for the app you want to reload, and then click Install again.
Takes a few minutes, but it will work.
Now, since you are new, you need a Toolbox of apps.
follow this link and get these setup. you will need them.
Note that Poster #2 works at a phone store and agrees with me on this.
make backup copies of your phone with Kies 3.0 ( and keep Kies updated ) every day or so until you get it all the way you want it.
During the early stages of fixing our phones, we are making changes to them left and right several times a day. i make backups 2 or 3 times a day when doing that. The backups are automatically Date/Time stamped.
* 3 tools you need to put on your S5 right now - Android Forums at AndroidCentral.com
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