I had this exact same problem when trying to buy a bunch of Ubiquiti gear last month that all had promo codes. I contacted their support as they should be able to dig deeper and provide an actual error code. Their support was unable to solve the problem, responding with the same boilerplate, you can't use Paypal for these types of purchases or these shipping options, none of which applied. I attempted to use both my Paypal Credit and an actual credit card. No dice. It really looks like Newegg is blocking it on their end. Perhaps because they have their own credit card and financing options now??? Regardless, I gave up on that purchase. Now, here I am today with a completely different cart, two promo codes, and the exact same results. Any time I try and checkout with Paypal, I get the same error message. It would be nice if Paypal and Newegg would, together, research what is actually happening. Is this a bug, or is it by design to prevent us from using Paypal. Honestly, on my end, it looks like that later. And that's unfortunate.
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