House move disaster

[#1]

OK, either the router has truly twisted knicker elastic or you have a "stale session".
You will need PN support to check out the latter and fix it.
You could do a factory rest on the router (this is loose and customised setup).  Take a paper clip and poke it in the small hole on the back of the router marked "reset" and hold it in for 10 seconds.  When you release it, the router will reboot and should be as clean and pure as the day it arrived.  It should then reconfigure itself - this will take around 15 minutes.

[#2]

I've done a factory reset today and I tried it yesterday, would it help if I tried to connect my old router instead? It's in the attic but if it will get me back online it's worth getting dusty looking for it.
Or would I be better to get PN support to fix this stale session before I face armed combat with attic spiders? 

[#3]

Being brave and facing the spiders would bring you to the conclusive point of confirming the issue is "with someone else".
If that is where you get to, it might be quicker to log into the user portal and try using the chat-session service rather than sitting on the phone.
...unless someone in CRT on the late shift spots this thread?

[#4]

I'll check cupboards for the old router before I don my suit of armour and climb into the attic.
If that fails I'm probably best calling PN, my phone data connection might stutter in a chat situation and I'm frustrated enough as it is.
Thanks again for your help, maybe I'll get this sorted out tonight one way or another.

[#5]

So, I found my old router without the need for spider combat, but that's the only good news. Once set up, factory reset and switched on, I got exactly the same result as with the new router.
One new development, at some point a warning from the computer popped up. It states:
Windows has detected an IP address conflict.
Another computer on this network has the same IP address as this computer. Contact your network administrator for help resolving this issue.
I don't know if that makes any difference to the problem but I guess it's now time to call PN support.

[#6]

No, that is completely local.
Did you go into the "found" router and set the PPP account details up afresh?  Or did you just pop it on the line hoping it will work? 
I rather suspect that the "found" router defaults to IP address 192.168.1.1 whereas the TG is 192.168.1.254 and dishes out addresses starting at 1.1.
I suspect that (having not restarted all of the devices after installing the found router, one having the address 192.168.1.1 given out by the TG is now conflicting with the "found" router.
...I hope that makes sense?

[#7]

Yep, that makes sense. I didn't think of that 
Anyway, I called support and, amazingly, got through to someone immediately  😮 he checked the website information on my plight and said that the engineers had 'done something' and that I should power off the router for 65 minutes before trying again. Apparently it takes an hour for the line to reset itself after the work done on it. So this will be my last attempt for tonight (with the new router back in place), if this doesn't work I'll be back on the phone again in the morning.
Thank (deity of your choice) for this forum! 

[#8]

Waiting for two hours after turning off the route made no difference, there's no change to my situation. So, back to the phone I go. 

[#9]

And this goes from bad to worse.... I called Plusnet support early this morning and was told that an engineer would, once again, need to come out to try to fix my new problem. I was told, on the phone, that this would be Monday or Tuesday next week. I awake a few hours later to an update to my Question, stating that an engineer would arrive on the 5th of January!
So well done Plusnet, you've managed to return my state of mind back to livid/furious just in time for Christmas. I think I'd better cancel all my Christmas visits, meals and parties, my Christmas spirit is locked in the exchange this year. 

[#10]

Did the PN communication explain why an engineer visit is required to address a PPP issue on ADSL?
Is the router getting xDSL up?  If it is, I do not understand what an engineer visit is intended to achieve.  From what you have described previously, this has all of the hallmarks of a PPP session authentication issue.
Any chance of you obtaining and posting stats from here - http://192.168.1.254/cgi/b/dsl/dt/?be=0&l0=2&l1=0 - and here - http://192.168.1.254/cgi/b/is/_pppoa_/ov/?be=0&l0=2&l1=2&name=Internet - if using the TG router please?  Note: Mask the user name details if they are yours and (if present) the IP address.

[#11]

First, I don't know what 'xDSL up' means 
The PN support chap didn't explain anything about the fault or why an engineer was needed. I didn't know if this was 'a PPP issue on ADSL' because, to be honest, I have no idea what that means and wouldn't have been able to explain myself if I quoted that to him. I'm perfectly happy to call them back and relay your explanation of it to them, word for word if need be. If you think it would help I'll call tech support and say whatever you want, I have no clue what's going on here   
Now, the two links you asked about, I can attach screenshots from my Nexus 7, I hope that's okay for this.
If I haven't done this correctly, try the ELI5 approach, please 

[#12]

EXCELLENT!!!
Indeed perfect!
From what you have posted, I do not understand why the CSC agent has requested an engineer, but I do not know everything!  I wish my line was as good as your line - you have perfect synch for a 20CN service.
Your problem is getting the PPP session established.
Explanation - There are two "links" involved in connecting a user to the internet...
SYNCH - depending on your product that is ADSL or VDSL hence the reference to xDSL.  If you have "synch" to the exchange xDSL is said to be "up".  You have perfect synch and zero error rates.
PPP - this a "virtual" connection between your router and your ISP - in this case PlusNet.  This is how your router "logons onto" PlusNet.  Did you notice the "Authentication Failure" message?
On the screen you posted, you need to put plusnetaccountname.plusdsl.net into the user name field and your account password in the other, then click connect.
I'm going to see if I can get CRT to poke this issue.  Please post back if you are successful in connecting.

[#13]

Alright! Brownie points for me! 
I have put in my username and password countless times in the last few days but to no avail  it refuses to connect. The 3rd screenshot shows what happens after I've applied my username and password, nothing  it says 'retrying' but nothing happens and it certainly doesn't connect.
I don't know if there's anything else I can do, is this something they can fix at PN's end? Rather than getting yet another engineer out here? I've no problem with sitting in the phone queue for a good while if I have something to give them which might fix my issue.
Again, thanks very much for your help and patience.

[#14]

I have asked some questions for you.

[#15]

Thanks, I'll sit here with everything crossed