If all the above steps have failed to get the Wi-Fi performance of your Android device back to the state that it was before installing Marshmallow, you are only left with one solution: do a factory reset. While extremely cumbersome, doing a factory reset will eliminate any issues with the radio or software itself. Since a factory reset will wipe your phone of all data, it is recommended that you create a backup beforehand. You also have the option of taking the device back to one of our Sprint store to get it repair.
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Actually, this problem existed in V5 lollipop as well. I was hoping that V6 MM would fix it. After the update and I continued to have the problem did I start the question in the forum.
I have no idea where to go next. It's really eating into my sprint data plan as every time my connection hangs, I have to switch off WiFi to get my apps/data to refresh.
you might have a lemon on your hand. unfortunately that happens with electronics. Maybe your WiFi card is not strong to keep a connection.
I have exactly the same issue with my Note 5. Ever since I installed MM, I can't keep a wifi connection. I know it had to do with the update, because it only started occurring when I updated: It was fine before that.
Please try forgetting the Wifi networks and connecting to them again.
To do this, follow the steps below:
Note: To connect to the Wifi networks again, the password will be required.
Please let us know if this helps.
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Here I am again....it "seems" some type update/fix came through the wife's Samsung Note5 for MM that caused even more problems, now the screen won't come on at all, can't call out and all calls automatically goes to her voice-mail... and the phone is charged. Man, this MM update for her phone is really giving me the blues.....
No OS update was sent through from Sprint, the only update was the security update that should have not touched any settings on the OS.
I would strongly suggest to put your phone in safe mode and try to use WiFi and calls. See if you have any issues. If you don't, that means you have a bad app you downloaded that somehow interferes with your OS.
If you still have issues, that unfortunately you will need to backup your phone and do a factory restore in it.
Make sure you do not instal any apps. until you phone has done all the updates and activation.
I hope this helps.