It has a new battery but as I try to register, it does not recognize

Hi,

Try using the tablet as close as possible (<30cm) to your WiFi network router and check if it now detects the WiFi network OK.

If it does then there is an antenna problem in the tablet.

If the problem has been there since the battery was replaced then perhaps the antenna became disconnected during the repair.

Check if the antenna is securely connected to the systemboard

Here’s the ifixit Nook HD+ Antenna Replacement guide. The image in Step.6 of the guide shows the antenna connected to the systemboard.

It is only plugged in at this end. The other end of the antenna is soldered in.