I'm surprised by this.. with Comodo having offices in China and even having AV analysts & developers there, I would have thought that they would better served/supported (infrastructure wise).
sdfsadfdfs, as you're probably aware URLs like download.comodo.com are not really what they seem. They're meant to identify the users geographical location and then route the users request to the nearest physical server location. Saying that, I've read through this topic & I may have missed where you said it (sorry if I did), but are you using anything that could hide/mask your geographical location (VPN, Anonymizer service, etc)?
I don't know what the comodo's offices in China are doing...

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