TP-Link TL-MR6400(ACAP) V5.2 Can't Revert Original Software

I Have TP-Link TL-MR6400 V5.2,and I install Openwrt,But 4G modem Is not working,i decide restore to Original Software,so i followed all guide about "TP-Link Openwrt restore original sorftware".

Everything seems fine,but i get much error.

i download TP-Link TL-MR6400 V5.2 Original Software(V5.20_210115) it .bin size is 62.5 MB,i use tftpd64,set complete parameter(ip,mask and bin name(tp_recovery.bin))

it show a error message Timeout waiting for Ack block,Remove power and plug it back in it just repeatedly blinks the power LED and all LEDs,so i change another way.

i use WinSCP put the Original Software bin in the router,it show a error message"scp: /tmp/original.bin: No space left on device,i check dir,file is upload,but size is only 28 MB,after i use dd if=original.bin of=tp_recover.bin skip=1 bs=512 count=16000 at Putty,it show a error message
dd: error writing 'tp_recover.bin': No space left on device
1+0 records in
0+0 records out

so...Until now, I have been using the mobile base station of my mobile phone to share to MR6400 to bridge the Internet, but it is very stuck, I don't want to continue like this, please help me.

I from Taiwan,My English is Bad,Sorry!

Modem would probably not work in openwrt out of the box, need to set it up.

Make sure the firewall's down on the host running the TFT server, you could
also try putting a switch between the computer and the router.

The dd activity should probably be run on some other host, than the router,
but there's no dd info on the device page.
But since your device only have 64MB RAM, and /tmp will be 50% out of it,
there's no way you can fit a 60+MB file there.

Been there, was almost hit by a rock coming down the hill, while driving back to Taipei, on the east coast :slight_smile:
Pretty sure I managed to get a speeding ticket too :slight_smile:

i already close my windows firewall,he does transmit,But tftp64 always show error at the last minute.

i think is bin file size is huge.

According to your description, means that I can't recover it to Original Software?

By the way, now it's a switch mode,but this is not it job,I really want to get him back to the original firmware.

The only way of knowing for sure, why this happens, would be to read the serial console log.
The bin file might actually contain a fw update for the modem too, hence the size.

TFTP is pretty safe recovery, assuming to does what it's supposed to.
I'd try that switch in the middle fix, if possible.

Is it possible to go back to OpenWrt?
Others have successfully activated the internal modem. Not sure if it was V5.2.

Probably you're doing somethign wrong?
Ensure the OS firewall isn't blocking tftp. Also try tftpd32 instead.

Sorry...I know what you mean, but I don't want to use Openwrt as my main system, because Openwrt is too hard for me,so the reference documentation is relatively less

Exactly, if I can successfully install Openwrt using tftp64 that means my setup should be correct.

The point is that the operations in it are skipping too much for me, so I'm getting an error about the 'dd' instruction

And about tftp32,i will try tonight

But don't recover using Openwrt, use the bootloader recovery method.
Otherwise the dd error message makes no sense!

There isn't enough memory in Openwrt to load such big file.

Ok,i try tftp32,But i got some tftp64 error like image.

IP :

Assign the correct server interface and try again (The one wih IP)

if the interface changes mid transfer, put a switch between the server and the MR....

i alway set it ip :

you need to run: dd bs=512 skip=1 count=16000 if=ArcherMR6400_stock_firmware.bin of=tp_recovery.bin outside the router and tftp the created tp_recovery.bin to your router, or did is that what you did?

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Sorry,i'm a new,it show this error ,and tp_recovery.bin is Openwrt recovery bin?or original recovery bin?
and i need copy which file to inside the router?
by the way,original recovery size is 62.5 MB

i just know,if i need use tftpd64 upload bin i need to change bin name to tp_recovery.bin.

Is there a detailed step that can guide me?

i just put Original Software in router inside,and it show

/tmp/original.bin: No space left on device

Follow the link @dabyd64 posted, TP-Link TL-MR6400(ACAP) V5.2 Can't Revert Original Software - #6 by dabyd64
Download and preparation needs to be done outside OpenWrt. Then the created tp_recover.bin can be tftp to your router.

yes,i know this,and i read it three time,But make me confuses me is that it doesn't say what file tp_recovery is or put where, and it doesn't mention where to put original.bin.

So that's why I still haven't finished restoring the original software

hi i'm back
After my last post, I went back to sort out all the references, and the next day I made it!!!!!!

I record the detailed steps here:

  1. First download the original firmware from TP-Link and name it original.bin

  2. You need a Linux-based operating system (I use Hyper-V, Ubuntu), and put the file in it (the storage space needs to be larger than the file)

  3. Use cd to find the folder of the file

  4. Use dd if=original.bin of=tp_recovery.bin skip=1 bs=512 count=16000

  5. tp_recovery.bin (about 8MB) will be generated in the folder

  6. Download it to your computer

  7. Set ip to
    mask is

  8. Use tftp64 to set ip and folder

  9. Remove the power of the router

  10. Press and hold the restart button before plugging in the power

  11. tftp64 will upload tp_recovery.bin

  12. Wait for the router settings to complete

  13. Connect to

  14. Done!


thank you for getting back, btw dd is available for Windows too, as a cli tool.

@mrhaav perhaps the stripping should be added to the wiki ?

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