I use a Samsung Galaxy Tab 2 7 inch. I go to my settings and I connect to my home wifi. But whenever I try to use Google apps that need Wi-Fi, like Google Play, it doesn't work. I tried cfixing my time, but that didn't work. And I tried to delete and re-add my google account, but when I tried to re-add it, it said "Couldn't sing in. Can't establish a reliable connection to the server. This could be a temporary problem. Try again or connect to another Wi-Fi network" It has been going on for 2 weeks, so I don't think it's temporary. I also have all 5 bars full, and it still doesn't work. Hope someone can help me 
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