Nobody can figure out what is going on here, so I am appealing to the OZBARGAIN knowledge base! No solution from googling! Here are the facts:
I bought a stylus pen from Ali Express (!!) ( https://vi.aliexpress.com/item/1005007552021473.html ) which was advertised to be compatible with my Surface Pro 7+.
The pen does NOT work on my Surface Pro 7+ (however touch screen works with my finger)
So, I took my computer and pen to HN to test it on demo Microsoft Surface computers (latest models I assume).
My pen worked on all HN Surface computers and also on all HP and Lenovo computers it was tested on (no pairing or setup required)
The genuine Microsoft pens attached to all the HN Surface computers all worked on MY Surface computer (no pairing or setup required).
BTW. My pen does not appear to have a pairing mode.
So why doesn't MY pen work on MY computer, even though it works everywhere else? The HN staff were baffled also even after 30mins of trying to figure it out!
HELP !!
I've come across this dozens of times when managing large fleets of Lenovo laptops and Surface Pros in schools. A particular pen won't work with a particular device. Pen works with all other devices, and all other pens work with the original device. It's not software/drivers as the same behaviour exists in BIOS, hardware test etc. I've raised numerous tickets with Lenovo, Microsoft, and their authorised repairers across nearly a decade and have never come across an answer.
In a school it's an easy fix because student happily just swap pens with another student :)
I've also seen the same thing with USB-C docks. Suddenly a dock will stop working with one laptop, and the solution is to swap it with one in another office…