Scroll down and read 'Adobe’s Own ‘Proof Of Purchase’ Isn’t Proof That I Purchased My Software' (Nov. 28th) as a all-too-typical experience with Adobe Customer Service.
I accidentally received a mac version of photoshop instead of pc. It said mac on the receipt as well even though I recalled ordering otherwise. While Adobe was on the phone with me I emailed a scanned copy of my receipt. The person then walked me all the way through the website pages transferring my license to a pc version and eventually gave me a new serial number. All in real time during the same call. For $5, they mailed me a disc for the pc version. Given the amount of money at stake, it went through as smoothly as I could have hoped for. Definitely keep your receipt in the physical box.