I called ATT UVerse service for a problem with my modem and they promptly shipped me a replacement which I have installed. The new one came with a power supply which I did not use because my earlier modem was connected to the ATT supplied Belkin battery backup - so I connected the new one to that too.
The instructions state that I should return the old equipment with the power supply - but I don't have one for the old modem. Should I return the power supply I got with this new modem when I take the old one to the UPS store?
I would first make sure that your new router works properly while plugged into the Belkin BBU just in case the problem with your old router was power related.
If you still have grief then try and run the router on the supplied power supply instead of the BBU.
If all good then yes just return the new power supply with the old router.
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