RT-N66U stuck in recovery mode - firmware fails

[Super Bee]

Originally had Tomato working fine on router. Decided to flash Merlin then ran into problems.

Cannot flash any firmware (including ASUS official) using ASUS restoration tool. Connected ethernet cable to LAN port which strangely shows up in network as old SSID from Tomato? Already done reset and 30-30-30 reset. Cleared NVRAM numerous times in ASUSTeK - CFE miniWeb Server and rebootted from screen. The router stays in recovery mode (power light slowly flashing), but I keep ending up with the firmware not completing through the ASUS firmware restoration utility. It starts to go then fails through upload.

 

[ColinTaylor]

I never had much luck using the restoration utility on my N66U but the CFE miniweb server worked eventually.

Ignore the timing messages on the screen, with the N66U you have to wait a long time for it to flash, something like 45 minutes.

 

[RMerlin]

The RT-N66U has slow flash, and the firmware is quite large. It can indeed take up to 40-45 minutes in some cases for the recovery to complete.

 

[Super Bee]

I never had much luck using the restoration utility on my N66U but the CFE miniweb server worked eventually.

Ignore the timing messages on the screen, with the N66U you have to wait a long time for it to flash, something like 45 minutes.

So you are saying rather than using the restoration utility to go through the CFE and upload the firmware there? I wasn't aware that could be done for fear of mucking this into a useless brick. Can this be with any other than the ASUS or does that have to be flashed first before going with Tomato, DD-WRT or Merlin? I don't recall this being such a bother when I flashed this four years ago when it was new. Thanks

 

[ColinTaylor]

So you are saying rather than using the restoration utility to go through the CFE and upload the firmware there?

Yes. First reset the NVRAM and then just browse to the firmware image and upload it. After a while you'll probably get a timeout message (IIRC). Just ignore it and carry on waiting for at least 45 minutes. That's where I went wrong, after 30 minutes I'd assumed it hadn't worked and turned off the router to try again. I just didn't wait long enough.

Can this be with any other than the ASUS or does that have to be flashed first before going with Tomato, DD-WRT or Merlin? I don't recall this being such a bother when I flashed this four years ago when it was new.

I don't know whether this works with other firmware because it's not something I've tried.

EDIT: I've just realised that you haven't said what firmware you were trying to flash. I was going from the latest version of Merlin (which has certain restrictions on what you can subsequently flash) to Johns fork. I suggest you try to load Johns fork first. From there you should be able to go to another firmware via the normal method.

 

[Super Bee]

I don't know whether this works with other firmware because it's not something I've tried.

EDIT: I've just realised that you haven't said what firmware you were trying to flash. I was going from the latest version of Merlin (which has certain restrictions on what you can subsequently flash) to Johns fork. I suggest you try to load Johns fork first. From there you should be able to go to another firmware via the normal method.

Okay mate I'll give this John's Fork distro a go. Never used Merlin before so I haven't any experience with it. I started all this third party firmware with my Linksys WRT54G. I first flashed DD-WRT then HyperWRT Thibor and lastly (which I am using to write this) Tomato Polarcloud. So mostly been used to the Tomato interface. I just want this to work so I really don't care what firmware is to be used.

 

[Super Bee]

Seemed to work out well! The interface says (Merlin fork) 374.43_2-20E9j9527
Thanks again to both of you!