I think I've found the problem (or solution).
When the password length is less than 8 characters, then the softAP(ssid, password) will NOT set to the given ssid. The command will only work if the password length is 8 characters or more.

Please verify that this is the case.

I read in other posts that v2.0.0 has fixed the problem with softAP not changing the ssid and/or password. It was working for me last week, but now it is no longer working. Whatever ssid I use in the WiFi.softAP command, the WiFi I get is always the original ESP_DAFA99. I'm using Arduino IDE v1.6.7. How should I debug this?
The relevant part of my set up code is just the standard...

char ssid[] = "ABC";
char password[] = "123"
WiFi.mode(WIFI_AP);
WiFi.softAP(ssid, password);
server.begin();