Samsung N910A at&t IMEI Repair Succesful
 

Gain Temporary Root with Kingroot apk (temporary: every time you reboot you have to root again)

INFO : 4/1/2016 5:22:02 PM > Platform: Samsung Android
INFO : 4/1/2016 5:22:02 PM > Selected port: COM15
INFO : 4/1/2016 5:22:02 PM > Selected model: SM-N910A
INFO : 4/1/2016 5:22:02 PM > Port is busy
INFO : 4/1/2016 5:22:06 PM > Phone was not found on the selected port!
INFO : 4/1/2016 5:22:06 PM > Searching for USB diagnostic port...
INFO : 4/1/2016 5:22:06 PM > Connecting to phone on COM57
INFO : 4/1/2016 5:22:06 PM > Mode: Normal
INFO : 4/1/2016 5:22:06 PM > Phone model: SM-N910A
INFO : 4/1/2016 5:22:06 PM > Firmware compiled date: Aug 12 2015
INFO : 4/1/2016 5:22:06 PM > Firmware compiled time: 12:00:00
INFO : 4/1/2016 5:22:06 PM > Firmware released date: Sep 3 2015
INFO : 4/1/2016 5:22:06 PM > Firmware released time: 10:58:23
INFO : 4/1/2016 5:22:06 PM > Phone IMEI: 356204-06-710345-5
INFO : 4/1/2016 5:22:06 PM > SW version: MPSS.DI.3.0.c5-00429-M9625TAARANSZM-1.26882.1
INFO : 4/1/2016 5:22:06 PM > Performed by 2.2.3 software version
INFO : 4/1/2016 5:29:28 PM > -----------------------------------------------------------------------------------
INFO : 4/1/2016 5:29:29 PM > Platform: Samsung Android
INFO : 4/1/2016 5:29:29 PM > Selected port: COM57
INFO : 4/1/2016 5:29:29 PM > Selected model: SM-N910A
INFO : 4/1/2016 5:29:30 PM > ADB server killed.
WARN : 4/1/2016 5:29:31 PM > Please, press "OK" button on the phone to allow USB debugging..
INFO : 4/1/2016 5:29:34 PM > Detected phone model: SM-N910A
INFO : 4/1/2016 5:29:34 PM > Firmware compiled date: Thu Sep 3 20:19:26 KST 2015
INFO : 4/1/2016 5:29:35 PM > PDA version: N910AUCU2DOI2
INFO : 4/1/2016 5:29:36 PM > CSC version: N910AATT2DOI2
INFO : 4/1/2016 5:29:36 PM > SW version: N910AUCU2DOI2
INFO : 4/1/2016 5:29:38 PM > Android version: 5.1.1 (LMY47X)
INFO : 4/1/2016 5:29:38 PM > Reading info...
INFO : 4/1/2016 5:29:38 PM > Mode: Normal
INFO : 4/1/2016 5:29:38 PM > Firmware compiled date: Aug 12 2015
INFO : 4/1/2016 5:29:38 PM > Firmware compiled time: 12:00:00
INFO : 4/1/2016 5:29:38 PM > Firmware released date: Sep 3 2015
INFO : 4/1/2016 5:29:38 PM > Firmware released time: 10:58:23
INFO : 4/1/2016 5:29:38 PM > SW Version: MPSS.DI.3.0.c5-00429-M9625TAARANSZM-1.26882.1
INFO : 4/1/2016 5:29:38 PM > Backup saved as C:\Program Files (x86)\Octoplus\Octoplus_Samsung\BACKUP\QCN-SM-N910A-01-04-2016_17-29-38-.qcn file
INFO : 4/1/2016 5:29:38 PM > Checking Root:
INFO : 4/1/2016 5:29:41 PM > Phone is Rooted.
INFO : 4/1/2016 5:29:41 PM > Reading security backup, please wait...
INFO : 4/1/2016 5:29:42 PM > Performed by 2.2.3 software version
INFO : 4/1/2016 5:29:52 PM > -----------------------------------------------------------------------------------
INFO : 4/1/2016 5:29:53 PM > Platform: Samsung Android
INFO : 4/1/2016 5:29:53 PM > Selected port: COM57
INFO : 4/1/2016 5:29:53 PM > Selected model: SM-N910A
ERROR : 4/1/2016 5:29:53 PM > Proper android device not found. Make shure that "USB debug" option on the device is turned on.
INFO : 4/1/2016 5:29:53 PM > Performed by 2.2.3 software version
INFO : 4/1/2016 5:29:59 PM > -----------------------------------------------------------------------------------
INFO : 4/1/2016 5:30:00 PM > Platform: Samsung Android
INFO : 4/1/2016 5:30:00 PM > Selected port: COM57
INFO : 4/1/2016 5:30:00 PM > Selected model: SM-N910A
WARN : 4/1/2016 5:30:00 PM > Please, press "OK" button on the phone to allow USB debugging..
ERROR : 4/1/2016 5:30:00 PM > Proper android device not found. Make shure that "USB debug" option on the device is turned on.
INFO : 4/1/2016 5:30:01 PM > Performed by 2.2.3 software version
INFO : 4/1/2016 5:30:17 PM > -----------------------------------------------------------------------------------
INFO : 4/1/2016 5:30:18 PM > Platform: Samsung Android
INFO : 4/1/2016 5:30:18 PM > Selected port: COM57
INFO : 4/1/2016 5:30:18 PM > Selected model: SM-N910A
INFO : 4/1/2016 5:30:19 PM > ADB server killed.
INFO : 4/1/2016 5:30:20 PM > Detected phone model: SM-N910A
INFO : 4/1/2016 5:30:20 PM > Firmware compiled date: Thu Sep 3 20:19:26 KST 2015
INFO : 4/1/2016 5:30:21 PM > PDA version: N910AUCU2DOI2
INFO : 4/1/2016 5:30:21 PM > CSC version: N910AATT2DOI2
INFO : 4/1/2016 5:30:22 PM > SW version: N910AUCU2DOI2
INFO : 4/1/2016 5:30:23 PM > Android version: 5.1.1 (LMY47X)
INFO : 4/1/2016 5:30:23 PM > Reading info...
INFO : 4/1/2016 5:30:24 PM > Mode: Normal
INFO : 4/1/2016 5:30:24 PM > Firmware compiled date: Aug 12 2015
INFO : 4/1/2016 5:30:24 PM > Firmware compiled time: 12:00:00
INFO : 4/1/2016 5:30:24 PM > Firmware released date: Sep 3 2015
INFO : 4/1/2016 5:30:24 PM > Firmware released time: 10:58:23
INFO : 4/1/2016 5:30:24 PM > SW Version: MPSS.DI.3.0.c5-00429-M9625TAARANSZM-1.26882.1
INFO : 4/1/2016 5:30:24 PM > Backup saved as C:\Program Files (x86)\Octoplus\Octoplus_Samsung\BACKUP\QCN-SM-N910A-01-04-2016_17-30-24-.qcn file
INFO : 4/1/2016 5:30:24 PM > Checking Root:
INFO : 4/1/2016 5:30:24 PM > Phone is Rooted.
INFO : 4/1/2016 5:30:24 PM > Reading security backup, please wait...
INFO : 4/1/2016 5:31:39 PM > Backup saved as C:\Program Files (x86)\Octoplus\Octoplus_Samsung\BACKUP\Security-SM-N910A-01-04-2016_17-30-24-.asec file
INFO : 4/1/2016 5:31:39 PM > Wiping EFS...
INFO : 4/1/2016 5:32:31 PM > EFS wipe successfully
WARN : 4/1/2016 5:32:32 PM > Phone will restart now. Please don't disconnect cable!
INFO : 4/1/2016 5:32:32 PM > Searching for a phone. Please wait...
INFO : 4/1/2016 5:33:02 PM > Reading info...
INFO : 4/1/2016 5:33:03 PM > Mode: Normal
INFO : 4/1/2016 5:33:03 PM > Firmware compiled date: Aug 12 2015
INFO : 4/1/2016 5:33:03 PM > Firmware compiled time: 12:00:00
INFO : 4/1/2016 5:33:03 PM > Firmware released date: Sep 3 2015
INFO : 4/1/2016 5:33:03 PM > Firmware released time: 10:58:23
INFO : 4/1/2016 5:33:03 PM > SW Version: MPSS.DI.3.0.c5-00429-M9625TAARANSZM-1.26882.1
INFO : 4/1/2016 5:33:03 PM > Wipe security successfully complete.
WARN : 4/1/2016 5:33:04 PM > Phone will restart now. Please don't disconnect cable!
INFO : 4/1/2016 5:33:04 PM > Performed by 2.2.3 software version

INFO : 4/1/2016 5:46:32 PM > Platform: Samsung Android
INFO : 4/1/2016 5:46:32 PM > Selected port: COM15
INFO : 4/1/2016 5:46:32 PM > Selected model: SM-N910A
INFO : 4/1/2016 5:53:33 PM > Selected file: I:\SAMSUNG N910A\Cert-sm-n910f_354780061169966.cert
WARN : 4/1/2016 5:53:39 PM > Perform the following steps:
WARN : 4/1/2016 5:53:39 PM > 1. Connect phone via UART cable to the Box.
WARN : 4/1/2016 5:53:39 PM > 2. Note: phone screen must be active
INFO : 4/1/2016 5:53:39 PM > Connecting to phone, please wait...
INFO : 4/1/2016 5:53:44 PM > Found phone on COM5
INFO : 4/1/2016 5:53:44 PM > Phone connected successfully
INFO : 4/1/2016 5:53:44 PM > Checking Certificate file...
INFO : 4/1/2016 5:53:44 PM > Certificate file successfully checked
INFO : 4/1/2016 5:53:44 PM > Writing new phone IMEI...
INFO : 4/1/2016 5:54:03 PM > Checking certificate compatibility...
INFO : 4/1/2016 5:54:03 PM > Certificate is compatible
INFO : 4/1/2016 5:54:03 PM > Writing Certificate...
INFO : 4/1/2016 5:54:10 PM > Certificate has been written successfully
INFO : 4/1/2016 5:54:10 PM > Please, restart the phone to apply changes
INFO : 4/1/2016 5:54:10 PM > Performed by 2.2.3 software version
INFO : 4/1/2016 6:00:47 PM > -----------------------------------------------------------------------------------
INFO : 4/1/2016 6:00:47 PM > Platform: Samsung Android
INFO : 4/1/2016 6:00:47 PM > Selected port: COM5
INFO : 4/1/2016 6:00:47 PM > Selected model: SM-N910A
INFO : 4/1/2016 6:00:47 PM > Reading info...
INFO : 4/1/2016 6:00:48 PM > Mode: Normal
INFO : 4/1/2016 6:00:48 PM > Firmware compiled date: Aug 12 2015
INFO : 4/1/2016 6:00:48 PM > Firmware compiled time: 12:00:00
INFO : 4/1/2016 6:00:48 PM > Firmware released date: Sep 3 2015
INFO : 4/1/2016 6:00:48 PM > Firmware released time: 10:58:23
INFO : 4/1/2016 6:00:48 PM > SW Version: MPSS.DI.3.0.c5-00429-M9625TAARANSZM-1.26882.1
INFO : 4/1/2016 6:01:03 PM > Send SPC...
INFO : 4/1/2016 6:01:04 PM > SPC send successfully
INFO : 4/1/2016 6:01:04 PM > Writing QCN...
INFO : 4/1/2016 6:01:04 PM > Writing NV items...
INFO : 4/1/2016 6:01:13 PM > NV items write successfully
INFO : 4/1/2016 6:01:13 PM > Writing NV SIM1 items...
INFO : 4/1/2016 6:01:13 PM > NV SIM1 items write successfully
INFO : 4/1/2016 6:01:13 PM > Wrting EFS...
INFO : 4/1/2016 6:01:23 PM > EFS write successfully
INFO : 4/1/2016 6:01:23 PM > Writing provisioning items...
INFO : 4/1/2016 6:01:27 PM > Provisioning items write successfully.
INFO : 4/1/2016 6:01:27 PM > Writing QCN done
INFO : 4/1/2016 6:01:27 PM > QCN write successfully
INFO : 4/1/2016 6:01:27 PM > Please, restart the phone to apply changes
INFO : 4/1/2016 6:01:29 PM > Performed by 2.2.3 software version

Thanks for good report! :)

Were can I download the certificate file can you please give me an idea

All IMEI Certs, which we have at the moment, are present on the Support Area.