Lenovo s850 root (mtk6582/4.4.2)

[aus9]

Your serial number has wrong number of characters as per

A 64-bit number (as a hex string) that is randomly generated when the user first sets up the device and should remain constant for the lifetime of the user's device

reference
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Its possible you did not know this.....and put in the wrong number of characters?
in which case Android will "null" the serial number. why not try again with the simple s/n as below in quote box---without the quotes?

OTHERWISE READ ON

I have googled and the serial number is set by init.usb.rc for some phones
firstly this is the string from your stock recovery but it was commented out with a #
meta_init.rc

write /sys/class/android_usb/android0/iSerial "0123456789ABCDEF"

On my system I could not find "iserial" so we may be better off first getting you to search and zip together all the normal boot up init<something>.rc files you can find.

upload it so I can have a look.

if iserial is mentioned in your rc files then we can set it by simple text edit
and yes look for that meta file first

if you find, feel free to use root to edit and then do a full reboot to test it.

good luck

reference see line 2 is set as a VARIABLE while you can make it absolute
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