Can't restore iPad 2,4 to iOS 9.3.5

[ALXANDERSOCOOL]

I can't restore my iPad back to the latest iOS (9.3.5) and I don't know why. Heres the logs from when i tried to restore it:

Verifying 'iPad2,4_9.3.5_13G36_Restore.ipsw'...
Checksum matches.
Extracting BuildManifest from IPSW
IPSW Product Version: 9.3.5
IPSW Product Build: 13G36 Major: 13
INFO: device serial number is DYTKLV2BDFHW
Device supports Image4: false
Variant: Customer Upgrade Install (IPSW)
This restore will update the device without erasing user data.
Checking IPSW for required components...
All required components found in IPSW
Extracting filesystem from IPSW: 058-49142-036.dmg
[==================================================] 100.0%
Getting ApNonce in recovery mode... ce 38 2a 46 3c a5 a7 6a 43 ca 31 0c e7 58 94 00 7c f6 ae ba 
Trying to fetch new SHSH blob
Getting SepNonce in recovery mode... 
Request URL set to https://gs.apple.com/TSS/controller?action=2
Sending TSS request attempt 1... response successfully received
Received SHSH blobs
Sending APTicket (2732 bytes)
Extracting iBEC.k93a.RELEASE.dfu (Firmware/dfu/iBEC.k93a.RELEASE.dfu)...
Not personalizing component iBEC...
Sending iBEC (283020 bytes)...
Getting ApNonce in recovery mode... ce 38 2a 46 3c a5 a7 6a 43 ca 31 0c e7 58 94 00 7c f6 ae ba 
Sending APTicket (2732 bytes)
Recovery Mode Environment:
iBoot build-version=iBoot-2817.60.2
iBoot build-style=RELEASE
Sending RestoreLogo...
Extracting applelogo.s5l8942x.img3 (Firmware/all_flash/all_flash.k93aap.production/applelogo.s5l8942x.img3)...
Not personalizing component RestoreLogo...
Sending RestoreLogo (5388 bytes)...
ramdisk-size=0x4000000
Extracting 058-49421-036.dmg (058-49421-036.dmg)...
Not personalizing component RestoreRamDisk...
Sending RestoreRamDisk (21602572 bytes)...
Extracting DeviceTree.k93aap.img3 (Firmware/all_flash/all_flash.k93aap.production/DeviceTree.k93aap.img3)...
Not personalizing component RestoreDeviceTree...
Sending RestoreDeviceTree (75532 bytes)...
Extracting kernelcache.release.k93a (kernelcache.release.k93a)...
Not personalizing component RestoreKernelCache...
Sending RestoreKernelCache (10618828 bytes)...
Waiting for device to enter restore mode...
About to restore device... 
Connecting now...
Connected to com.apple.mobile.restored, version 13
Device 0446d9d6a29a5495541cddfefd82a395d4b54748 has successfully entered restore mode
Hardware Information:
BoardID: 6
ChipID: 35138
UniqueChipID: 68460883405
ProductionMode: true
Starting FDR listener thread
ERROR: Unable to connect to FDR client (-2)
ERROR: Failed to start FDR Ctrl channel
ERROR: Unable to start the restore process
ERROR: Unable to restore device

On every OS and every restore tool (iTunes, 3uTools, OTA-iOS-downgrader) they all say "unable to connect to FDR client (-2).

[nikias]

Looks like you're using an older version, but regardless the reason it aborts is not the FDR Ctrl channel failure. The error ERROR: Unable to start the restore process points out that when telling the device to start the actual restore, something goes wrong. Maybe the options sent to the device are not accepted, but I was under the impression that this used to work, so no idea what is really wrong here. If iTunes can't restore the device, then it is probably something wrong with the device...