use my old airport extreme to extend the network, which I had been doing with the Time Capsule.
There are two ways for the AirPort Extreme to "extend" a network. It can connect back to the Time Capsule using a wireless connection.....or.....much better, it can connect back to the Time Capsule using a permanent wired Ethernet cable connection.
How was the AirPort Extreme configured?
We ask this because Apple's "extend a wireless network" setting is a proprietary feature that allows the AirPort to extend the signal from another Apple router using a wireless connection. But, this setting will not work with a 3rd party wireless router.
Which model of "old" AirPort Extreme do you have? Is this the current "tower" shaped model or an older "flat" or "square" version (that looks like a small white pizza box)?
If it is an older version, we need the model number. It's on the bottom of the AirPort, likely embedded in the foam pad base. The model number starts with an "A" followed by 4 numbers. Post back with that info.
The employee claimed he had done it and that it was simple.
It is.....if you are planning to connect the AirPort Extreme back to the TP-Link router using a permanent, wired Ethernet cable connection.
It is not simple....and in fact not possible.....if you are planning to connect the AirPort Extreme back to the TP-Link router using a wireless connection.
I haven't been back to the Apple Store to find him, and wondered whether anyone else knew how to do this.
Assuming that your AirPort Extreme is a current or recent model....we know how to do this using a permanent, wired Ethernet cable connection between the AirPort Extreme and TP-Link router.
But, we don't know how to do something that is not possible, so we'll assume that the employee was thinking that you would be using an Ethernet cable to connect the AirPort Extreme back to the TP-Link router.
Post back with the info that we requested, and we will continue.
Edit.....Looks like LaPastenague posted almost at the same time and before I posted. Sorry for confusion.