This is for the Galaxy S5 with the most current updates only. It may work (and I hope it does!) with other updates or models but I cannot guarantee that.
It repeatedly pops up "Unfortunately, Samsung Link has stopped working." When you click OK or Report, it pops up the same error again and again.... You get the point. And It appears that it's an app that's pre-installed are automatically updated/downloaded when you buy the phone new. I certainly never had it in "My Apps" on my S4 Active....
**Here's the Fix**
Between the error popping up literally every second, and you clicking OK, you can use the phone normally.
1. Click your multi-window button, click the pie-chart and "End all" applications.
2. Pull down your notifications tab. It's the only place safe from this bug.
3. Click settings, in the top right corner.
4. Scroll down to Application Manager and click it. It's located in the Applications subgroup at the bottom of the menu.
5. Where it says DOWNLOADED and SD CARD at the top of the screen, scroll right until you get to "RUNNING". Ensure it says "Show cached processes" in the top right corner. If it doesn't just click it til it does.
6. Somewhere in that menu.... I found it near the top of that menu on my phone.... there will be a process called "Samsung Link" that will repeatedly appear and disappear. It is fiendishly good at hiding but I PROMISE you, it is there. And sometimes it's rather slow at reappearing, so look carefully.
7. Click it. Try to hit Stop on either processes contained within then hit OK. It keeps failing and disappearing, so you must be persistent. Repeat..... I promise you this works.
8. Uninstall Samsung Link.
9. Curse Samsung for their incompetence.
Cheers, mates!
-Flea