Note 3, Android 4.4.2, forgets wifi password since an update 5 months ago my note 3 occasionally forgets my wifi passwords. Sjnce I have it set to jump to 4G cell data, I am accidentally using up my mobile data allowance.

This happens only every 2-3 weeks and I cannot find any logic to it.

Is there a way to see what has occured?

Any advice greatly appreciated.

PS. It is an Australian Telstra branded unrooted phone.
As always, there are several things that could cause this. I'm just trying to guess some:


Prior to Android 4.3 Wifi passwords were stored in a plain text file (no hash) on the device. In the beginning shell access was enough to get the passwords. Later on, they made it read only by system users.
Starting with Android 4.3 Samsung added this file to the Knox secure storage partition. If you have an (access) issue with knox or it's partition, the wifi password was lost. Even if you were never using Knox. It's also the only thing not working if you remove knox.
As fare as I know, google did something about the wifi passwords too in newer Android versions.
Perhaps you were changing a knox setting or password?
chances are high it's just a bug in the wpa_supplicant binary of your firmware, the csc or Samsung binaries.
Try to get latest updates.
do you loose all wifis stored? Or just one? Could it be your router?