I am getting this error message on a Xiaomi Redmi Note 2:
Can't get valid Device ID
Invalid Device ID: null
Device ID must be valid IMEI or MAC address. Without device id, some account and cloud features will be unavailable.
It pops up randomly, sometimes it appears several times (I click Ok to dismiss it) in a minute, sometimes it doesn't show up in about an hour. It interrupts apps and the phone (and all phone related features like sms) does not work, as it doesn't detect the sim card, which actually works, as I have tested it in another phone.
I woke up and this started happening suddenly. Usually the phone updates apps at night, so that might be it.
The following information might come useful:
- Model number: Redmi Note 2.
- Android Version: 5.0.2 LRX22G
- Android Security Patch Level: 2016-04-01.
- MIUI version: MIUI 7.4 by xiaomi.eu 6.5.5 | Beta
Note: This is the issue same issue as this one: http://en.miui.com/thread-109909-1-1.html
The solution given there does not fix the problem.