micro SDHC 64GB problem

Hi
I am having a problem with my new micro SD card on my D7100. As soon as I insert the SD adapter with the micro SD in it, the camera display says "[Err]". When I ignore this and try to format it with the camera, I get an error message and it says "Card might be defective".
The card works well in a computer or tablet. I also tried other micro SDHC in the camera, with less storage capacity, and it worked.
This is a HP micro SDHC of 64GB, class 10. The nikon page says they tried these memories only upto 32Gb (https://support.nikonusa.com/app/answers/detail/a_id/18248/~/approved-memory-cards---d7100). Does any body whether this card will work or not in d7100?
Thanks

SDHC only supports up to 32GB. 64GB would be SDXC. It is entirely possible that a camera as old as the D7100 doesn't support SDXC. I say this without having looked at the specifications to see whether the D7100 claims to support it or not.

My guess is that this is more likely related to the micro card in an SD adapter, than it is SDXC and 64GB. I regularly shoot with a 64GB SanDisk card with no issues.

The D7100 is more than capable of handling SDXC (considering it's not that old);
Nikon | Imaging Products | Specifications - Nikon D7100

I suspect the issue is more the microSD card you're using or the adapter or both.
Can you experirment with another card and holder to see which combo works.

Also, as mentioned already, SDHC is limited to 32GB, capacities after that are SDXC.
If you have a SDHC 64GB card - then that's the issue.

I use two 32gb micro cards with my D7100, both SanDisk Ultra (the red and black ones) and I got a card read issue a couple of times when reinserting in the camera and duh the little tab for copy protection slid halfway back. So double check that the little slider on the adapter is slid up or when inserting towards the camera slot. Could be something that simple but double check as it freaked me out at first as well. If not then probably a compatibility issue like people said.

This is just a matter of curiosity. Why use a micro SD card with adapter in the first place? The Full size SD cards are what it is designed for.