I have been experementing with my SGS4 and my Dlink DIR-655 router (used as access point). I find the problem comes from WPA with AES. Changing settings to TKIP only, and everything works just fine. Only problem is my computer don't get n speed using TKIP. Guess the Dlink is ready for the dustbin now. Have tried several firmwares for the router, all with the same problem. If the fault lays with Dlink or Samsung I don't know, but the S4 is the first to have these problems.
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