This is one of the things we did in trying to resolve the issue.
We determined that this is not necessary.
The Production servers (using WinHTTP), and CURL (which doesn't use WinHTTP) from any server, connect with no certificate at all, and there is no mention of one being needed in the documentation.
When using cURL, what error does it give you?
curl -G -H "Authorization: Bearer YOUR_API_TOKEN" https://api.clover.com/v3/merchants/MERCHANT_ID/items -d "limit=10"
None. cURL works properly and gives us the data. Microsoft WinHTTP request of the same page with the same headers gives us "Error: '213','WinHttp.WinHttpRequest: A certificate is required to complete client authentication".
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