Hi,

I have the same router, with the same router version and the same firmware, I tried to update with the same firmware update and got the same error message. When I tried to update the firmware, it was not over wifi.

Please post an update if you resolve the issue, I'll do the same.

What kind of internet browser are you using? Please try IE is this same error?

I've had a reply from tech support saying to upgrade first to 140305 (not UK specific), then to 140331.
I already found a chinese readme file in the 140331 zip which if translated seems to suggest the same thing, although I thought best to ask for clarification!
It seems 140305 doesn't appear for download if your region is set to "UK" on TP-Link website, it is available if region is changed to "Worldwide".

Haven't tried yet so don't know if it works....

Something else I noticed in the notes for 140305: [Note] The software itself is not digitally signed , only upgrade 3.0.0 Build 120524 Rel.05221 ( Part Number: 5020003658 ) previous software
I'm already on a higher version (3.0.0 Build 120808 Rel.28888 - what it came with - has never been available for download for some reason?)
So potentially it could mean a downgrade, then 2 upgrades :(

Would be good if TP-Link could clarify this and/or make an update for 3.0.0 Build 120808 Rel.28888 directly to TD-W8961ND_V3_140331_UK.

Hi,

The region was the key for me. I did not double check in which region I was downloading from. As soon as I chose Canada for the region and navigate back to the download area, the zip file I got there worked on my router.

So you updated to 140305, not 140331(UK) ?

Yep!

Firmware upgrade page now says:

Build 140305 Rel.04531

The previous firmware was 12xxxx, I can't remember the exact release date, but it matched yours.