728x s-off problem
 

Sending oem writesecureflag 0
... FAILPERMISSION DENY (SIGNATURE_FAIL)
FAILED (remote: PERMISSION DENY (SIGNATURE_FAIL))
Execution time is 1(s)
Operation finished
Reading information...
Using Fastboot mode...
Reading common information
(bootloader) kernel: lk
(bootloader) product: htc_a50cml_dtul
(bootloader) version: 1.0
(bootloader) imei: 357193073776801
(bootloader) version-main: 1.33.709.1
(bootloader) boot-mode: download
(bootloader) version-baseband: READ version-baseband ERROR
(bootloader) version-bootloader: 1.01.0000
(bootloader) mid: 2PQ811000
(bootloader) cid: HTC__621
all:
Execution time is 11(ms)
Reading secure flag information
... (bootloader) Device security level S-ON
OKAY
Execution time is 517(ms)
Reading CID information
... (bootloader) cid: HTC__621
OKAY
Execution time is 10(ms)
Reading MEID information
... FAILREAD MEID ERROR
FAILED (remote: READ MEID ERROR)
Execution time is 7(ms)
Read information failed

Sending oem writesecureflag 0
... FAILPERMISSION DENY (SELECT_APPLET_FAIL)
FAILED (remote: PERMISSION DENY (SELECT_APPLET_FAIL))
Execution time is 1(s)
Operation finished

Sending oem writesecureflag 0
... FAILPERMISSION DENY (GT_CONNECT_FAIL)
FAILED (remote: PERMISSION DENY (GT_CONNECT_FAIL))
Execution time is 1(s)
Operation finished

Sending oem writesecureflag 0
... FAILPERMISSION DENY (NOT_FIND_SMART_IO)
FAILED (remote: PERMISSION DENY (NOT_FIND_SMART_IO))
Execution time is 16(ms)
Operation finished

Sending oem writesecureflag 0
... FAILWRITE SECURE FLAG ERROR (10)
FAILED (remote: WRITE SECURE FLAG ERROR (10))
Execution time is 7(s)
Operation finished

Hello,

I don't even know what to answer you...
All possible problems in 1 minute?

About the last problem - please DO NOT press the button immediately.
I think you are trying to make everything too fast.
Let the phone boot and wait at least 5 seconds, then press the button and wait.

Also check your flex cable, it may be damaged, taking into account your errors.