I use the Samsung Galaxy S5, after the use of third-party ROM brush, often will appear after the restart cannot save password WiFi, every time you want to re-enter, very troublesome. After struggling to find finally found a solution: R.E. file manager into data/misc/wifi record for the WPA Wpa_suppliCANt.conf file, use a text editor to open and delete the content (such as not to perform this operation, WiFi will become gray not open). Then enter system, open build.prop with text editor, delete ro.securestorage.support=true.
After the operation is complete restart the phone, when the connection WiFi input again password, the restart will not prompt the password. Finally, to remind you, before deleting the file must do a good job backup, lest MIS operation.