[Samsung Galaxy Tab A series Questions & Answers] Casper Young:
There are 3 FRP Recovery Locks

This may be difficult to explain. I've been scouring all through XDA searching for an answer to a second issue and this apparently is a third. So here I need to back up. My first issue was after I rooted my T580. I was Beta testing and on a search and destroy mission with a root method that worked well, yet had a few bugs which I was correcting at the time. I had already provided a fix for the Samsung Security Agent for people to take care of the issue where the device ask users to reboot. And I have noticed it often doesn't charge while in use. In the Developer Settings the USB Configuration does not move from MTP to Charge, this one seemed a Settings issue that I noticed on my tab that no-one else mentioned. I also ran into a difficulty with going to Download Mode and this was yielding different issues. No Recovery was one of them. Others were mentioning a redirection to a locked FRP. I tried to replicate the issue only to be locked into Download Mode and couldn't flash nor leave.

I got out of that by holding the power, home and both volumes down until the device shut off and reset (about 20 seconds). After this I booted up again and the Device Manager was giving me a notification of some security threat asking for a restart. This was the Security Agent again. I turned it off and tried to reboot to recovery. I got redirected to a blue page with red letters at the top left saying, "Custom Binaries Blocked by FRP Lock". The symtoms are: Bootlooping, won't load past Logo screen and often flickers. Download mode is accessable but Odin3 is not flashing official firmware. Worst of all? Absolutely no Recovery. I flashed this in: SM-T580 Binary 4 FRP Unlock.

https://drive.google.com/drive/folders/1iXrZR2E7m6Ai5InAw8u3lzeLhb3ThRo5?usp=sharing

Incorrect or invalid files are the reason for this happening which overload the Binaries so they're blocked! Now this got me out of FRP Lock which ended my personal issue. Here's some things I picked up along the way that are useful,

This one clears Knox:

https://drive.google.com/file/d/1EolYe9auY9jslYSpSgHoon_YB00D2noV/view?usp=sharing

Here's an updated TWRP: (For the T580)

https://drive.google.com/file/d/125ucHgjdNYqs54k2EmiwJZY_KxTdsTMi/view?usp=sharing

And here's a patched Odin3.13B because the normal one has some difficulties:

https://drive.google.com/file/d/13c0uDH99PcUzO0cnHuyBKy2e-b_I1W53/view?usp=sharing

The second issue is with another tablet but very similar. having all the same symptoms but the recovery redirect doesn't say Custom Binaries blocked ect. It said:

Odin Mode

Download Speed

Fast

PRODUCT NAME: SM-T580

CURRENT BINARY: Custom

SYSTEM STATUS: Official

FRP LOCK: ON

Secure Download: Enabled

WARRANTY VOID: 1 (0x0500)

Frp is enabled.

Ignore pit partition

So far I can do nothing to correct the difficulty of the second FRP Lock. And here appears to be a third FRP Lock. This is unusual! It is not advisable to downgrade to 7.1 because of the differences in partitioning. And it's a serious consideration that whomever had the device before may have tried because it referrs to the pit files. I've tried many different methods, OEM Unlock, flashed the bootloader in, the BL, the BL and the AP, the 3 file (BL, AP & CSC) and the 4 file (BL, AP & Home CSC) and got nothing! But fixing the partition or pit files wasn't one of the methods.