The message I get from my Anti Virus/Firewall when Flash is trying to update :
FLASHPLAYERUPDATESERVICE.EXE cannot confirm the authenticity of fpdownload.macromedia.com as a trusted vendor.
I have been trying to solve this problem for the past week. I have gone through searches on Adobe, been directed to link after link only to find myself directed back to where I first started. I have uninstalled, used Adobe Customer Response Tool to try to pinpoint the problem but no matter what I have done the problem goes on. Also get another message that tells me 'Action List cannot be found'.
I have also had exactly the same problem with the Java Updates.
What anti virus vendor are you using? I'd recommend talking with them to find out how you can either add Adobe (and Oracle) to your trusted vendor list or disable that feature.
You might also want to try installing from our stand alone installer which you can find here: