I was offered a replacement. I went for a refund.

In reply to a post by jpm:

I would advise against buying Technicolor routers as they are only really designed to be sold to ISPs and integrated with their management platforms. You can't get software updates for them easily, or any direct support from the manufacturer.

I had a technicolor years ago in the ADSL days, it was called Thomson then, it was ok. I used it for different networks and it's done ok, but that was a long time ago and things may have changed, in fact things have changed

This may be a silly question but did the password have letters/digits that could be mistaken? For example a 0 or O, a 1 or l, etc, etc.

Not a silly question at all, Ian.

There were no zeroes and noughts or an "i" a "1" or an "l" in the password. The capitals were obviously distinguishable from the lower case letters except for a lower case “k” and a capital “K”. They could both have been upper case so I tried that variant before my first call to the vendor.

The user name supplied was “admin” but I tried “administrator”, “Admin” and “Administrator” before my phone call. Seemingly endless logins were tried during and after I spoke with the techiel before I rang a second time.

Sounds like you ruled out all of the obvious then. Possible it was the wrong label applied to the device at the factory.

I wondered about that...

I'm putting this here in case anyone else with the same problem finds this. I just had Trooli FTTP installed and was supplied this router. Couldn't login with the ACCESS_KEY provided on the sticker, which is also the same as the entry next to Password printed on the sticker (separate to the WiFI password).

I was very confused. Triple checked all the characters. Factory reset the unit. The firmware even has a visual reminder built in so that when you enter the password wrong it comes up with a picture of the ACCESS_KEY barcode and says that's the default password.

Well, I did a bit of googling and found something about a different Technicolor router and it said the default password was the serial number, which is not the same as the access key.

Went and tried that and hey presto, logged in. Technicolor have seriously stuffed up here and are going to cause loads of support calls to Trooli (and any other ISPs that are issuing these routers). I've let Trooli know.

So, in summary:

THE DEFAULT PASSWORD IS ACTUALLY THE SERIAL NUMBER AND NOT THE ACCESS KEY!! IGNORE THE STICKERS.

Thank you so much Slinkoff! I have been searching for a solution to this due to getting no response from the isp all week, came across your reply in this thread and it worked perfectly. How strange!
Thank you once again.

Had the same issue with a DGA4134 router, where I couldn't login to it. Tried all the things in this post. Found out the username to use is 'engineer' not admin.

In reply to a post by ARD:

I think I'd stick to my ISP or Amazon from now on. Anywhere else and it's tricky to get a refund.

And with Amazon, make sure it says "Sold by Amazon" (not "Dispatches from Amazon"). The rest of Amazon is now like a low-grade E-bay.