most videos won't play on all apps

[melodymae]

I have 2 galaxy tab 3's. Both habe problems playing videos. On all apps including youtube. It just gives me errors. It was working just last week. I don't know what happened. If anyone one could help that would be appreciated. They are both white I think the 8". The smaller version

 

[B. Diddy]

Welcome to Android Central! I assume they're on wi-fi. How are other web-connected services--any problems there? Have you tried using them on wi-fi networks other than your home?