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RT-AC66U B1 Unable to flash firmware error

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GemiNinja57

New Around Here
Hey all! I'm fairly new to all of this wrt stuff but I purchased an Asus router (RT-AC66U B1) specifically to flash Merlin and utilize the IPTracking info since my ISP has suddenly incurred a data plan in my area. I feel as though I've been searching for hours and can't seem to find any thread that resolves my issue. Any time I try to flash the newest FW version of Merlin I receive a "Invalid Firmware Upload" error message and I just can't seem to get past it..

I'm using the "RT-AC68U_384.4_2" driver and trying to flash through WebGUI.
I have factory reset, cleared NvRam and reboot the router several times.
I also disabled any firewalls that might be in the way and cleared my web browser cache.

I just can't seem to find a thread that directly resolves my problem and I'm not sure if I need to use the recovery tool to flash the Merlin f/w or just revert to an older Asus f/w version in order to flash Merlin (The router updated it's Asus f/w to the latest version 4.384_2).

Any help would be seriously appreciated since Merlin is essentially the only reason I chose this router in the first place xD. Thanks in advance!

EDIT: I flashed the SECOND to most recent BIOS once I noticed the newest had been released only days ago and once that finished I was able to flash Merlin with no problems! Problem solved, hopefully this helps some other noob who runs into this minor error xD
 
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I'd try it again cabled thru a LAN port and if still didn't work yeah, I'd do the revert to stock and try it from that.
 
Hey all! I'm fairly new to all of this wrt stuff but I purchased an Asus router (RT-AC66U B1) specifically to flash Merlin and utilize the IPTracking info since my ISP has suddenly incurred a data plan in my area. I feel as though I've been searching for hours and can't seem to find any thread that resolves my issue. Any time I try to flash the newest FW version of Merlin I receive a "Invalid Firmware Upload" error message and I just can't seem to get past it..

I'm using the "RT-AC68U_384.4_2" driver and trying to flash through WebGUI.
I have factory reset, cleared NvRam and reboot the router several times.
I also disabled any firewalls that might be in the way and cleared my web browser cache.
The AC-66 and N-66 routers are not supported by the Merlin 384 series firmware, and Merlin has dropped support for these models. You can download the latest version that supports these models (380.69_2). There is a final release coming soon (380.70), but there will be no further releases after that one. You can use John's fork of Merlin, which is still receiving updates, and can be found at https://www.snbforums.com/threads/fork-asuswrt-merlin-374-43-lts-releases-v31e6.18914/.

I have an AC-66, and am considering just going back to the ASUS stock firmware.
 
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OP is talking about the second generation AC66U which is still supported.

@GemiNinja57 babe you tried flashing with the specific ac66u b1 firmware and not the ac68u firmware?
 
Hi,
I bought the ASUS AC66U_B1 and I tried to install Merlin on it but it doesn't work at all, I've tried to get some help from friends but they couldn't manage to fix the problem.

One of them told me that I have to flash my asus with an OLD version first and after flash it again in order to activate the JFFS partition.

My actual version is 3.0.0.4.384_20648-g21e3702.
I tried to flash some old version from the official ASUS website but everytime I upload the file it told me that : "Invalid Firmware Upload" so I can't put an old version in order to put a nex one later to activate the JFFS partition.

Thanks for your help
 
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Sorry for this 'me too' but I'm in exactly the same boat as ElemenT... any help or advice out there? Would a factory reset help?

TIA
 
The AC-66 and N-66 routers are not supported by the Merlin 384 series firmware, and Merlin has dropped support for these models. You can download the latest version that supports these models (380.69_2). There is a final release coming soon (380.70), but there will be no further releases after that one. You can use John's fork of Merlin, which is still receiving updates, and can be found at https://www.snbforums.com/threads/fork-asuswrt-merlin-374-43-lts-releases-v31e6.18914/.

I have an AC-66, and am considering just going back to the ASUS stock firmware.


The RT-AC66U B1 is actually a 68U, silly of Asus to do that.
 
Even when I download the AC68U, nothing work :) and I tried MANY version of them, old or recent, always the same error that told me the Firmware is Invalid to upload !
And yes, I tried reset multiple time also haha
 
Hi, I;m runing 384.4_2 without any problem on my AC66U B1.
Same here with no issues, have uploaded a few versions over that past couple of months.
 

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