Connecting Canon MX340 to Router

[#1]

As a newbie to Plusnet, I tried to connect my all in one Canon printer MX340 to the Plusnet router but although the printer can see the router, it times out when trying to connect to it. I have pressed the button on front of the router for at least 5 seconds as the printer instructions suggest but  nothing happens. As far as I can see I have followed the printer instructions correctly to this point. This is my first foray into wi-fi so there is something that I should have done before trying to connect. Can anyone suggest what? My PC is using XP Pro SP3.

[#2]

Plusnet have supplied lots of different routers... what is the make, model and firmware version you are using.
Note: If this is the TG585v7 or v8, the button on the front does nothing.

[#3]

The router is a Thompson TG585v8 with a do nothing button
As to firmware I am not quite sure where to find this.

[#4]

Does the do nothing button mean I cannot connect  my printer to the router?  I wish to be able to print from two PCs.

[#5]

not familiar with Canon printers but on my HP WiFi was set up using a menu option on the printer fascia.
Set up WiFi, select the Thomson router from the menu, it will ask you for your password, use the password given on the bottom of the router or the loose label in your welcome pack.
Then install the printer as normal from the windows options.
Is this what you did

[#6]

Thanks for your continued interest. What you suggest is what I did try to do but the printer seemed to stop at the fourth digit. Maybe I will have to contact Canon, as I can't see a reference in the 107 page (!) manual.

[#7]

Looking at the Canon web site it would appear that they recommend installing the printer by temporarily connecting it via USB to a computer.
http://www.canon.co.uk/Support/System/Search.aspx?TcmUri=tcm:14-715288
This allows the printer driver software to be installed and also to configure the wireless security settings into the printer.

[#8]

Check this thread about my HP installation 
http://community.plus.net/forum/index.php/topic,97090.msg825889.html#msg825889
I have had my HP c309a working on Wifi Ethernet and USB