I have recently purchased an OEM COA with a refurbished PC and the COA has arrived in pristine condition on waxed paper (doesn't seem to have been removed from a PC). It has the interwoven strip, I have scraped some of the paper off and the strip is intact running through the paper but something doesn't quite sit right with me. I have another one here which is definitely legit, the printing differs very slightly between them but I guess that is plausible seeing as millions were produced but the genuine one has a gloss finish whereas the questionable one has a matte finish. I can't find any info on google whether it should be glossy or if you could get either. The glossy one doesn't have a plastic overlay, just a glossy finish which isn't consistent, kind of the finish you would get if you sprayed it rather than overlayed a gloss layer.
Any ideas? I haven't tried using the product key, I will return it if it turns out to be a fake.