SM-T307U stuck in EUB mode – loader error on Z3X Samstool 1.23

Question

Hello team,

I'm trying to remove KG State on a Samsung Galaxy Tab A 8.4 (model SM-T307U) using Z3X Samstool v1.23 with the Exynos7885 profile. The device enters EUB mode successfully, but the tool fails when sending the first loader. I’ve tried multiple loaders within the software and keep getting errors like:

Sending first loader... error(4.4.3)
Sending first loader... error(4.4.2.0)
Sending first loader... error(7.0000008c.1)
Device found, but cannot open
Reconnect your phone or restart your computer

I’ve already restarted the PC, reinstalled drivers, tried different USB ports and cables, but the issue persists. I cannot exit EUB mode or enter Download mode. The firmware currently installed is T307USQSACXA1 (TMB USA).

Could you assist me with this issue or let me know if a specific loader is required for this model/firmware?

Thanks in advance.

 

Answer 1

Hello. Hold power key diring sending loader.

 

Comments

It doesn't work, the error persists

Operation: Factory Reset Selected model: SM-T307U Software version: 1.29 Setting up enviroment... OK Waiting for EUB device... [Exynos7885] ... OK Sending first loader... error(4.4.2.3) Waiting for EUB device... [Exynos7885] ... OK Sending first loader... release power key... error(7.0000008c.1)

T307USQSACXA1

VZW