Samsung S5 Wifi not connecting automatically

Samsung S5 is a powerful Android mobile phone. In May 2015, the S5 received an update to Android 5.0 but has since had a problem with the wifi.

The smart network switch automatically switches from wifi when it gets weak, to mobile data. Usually, to save on mobile data its a good idea to turn it off. This way, even if wifi is weak it still stays on until signal is lost.

It can connect to wifi. However even after choosing smart wifi, it does not automatically reconnect when returning to the most wifi access point (AP) that it has saved the password. I say most because it can connect to open public wifi like Starbucks.

Previously, before the upgrade it was able to connect without problem.

Even resetting to factory did not help. Probably had something to do with me restoring my backup.

Here is how I got it working, clearing the S5 phone cache.

Step 1: Power off the S5

Step 2: At same time hold down following keys;
Volume up, power on/off, Home.

When it vibrates or see the galaxy start screen, release the power on/off.

Step 3: clear cache and restart
Use the volume key to select clear cache. Press the power button.

Once it says cache cleared, use volume button to select restart of phone and press power button.

Done.