How do I add a device back in?

[#1]

I decided to delete a detected device from the thomson gateway local network devices since for some reason I couldn't get it to connect. However I discovered after doing this that I don't know and can't seem to find out how I can re-add it.
What do I do?

[#2]

Quote from: tonyanewton8

for some reason I couldn't get it to connect.

I could be wrong but I think the router adds devices automatically as soon as it sees them.  So the network interface on your device must have stopped working.  That's the real problem.

[#3]

If necessary, reboot the router - unless you banned the devices hardware address setting permanently. 
If all else fails, you may have to resort to reset to factory settings. 

[#4]

Quote from: vilefoxdemonofdoom

... unless you banned the devices hardware address setting permanently. .

Some routers have a facility to construct a whitelist of device hardware (MAC) addresses that are allowed to connect over wireless.  Here is an old thread about this on the TG582n http://community.plus.net/forum/index.php/topic,111197.0.html/ ; .  So you might be able to ban a device (from connecting wirelessly) by turning on MAC address filtering and leaving the device MAC address off the list of allowed devices.
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