Flash player being blocked?
OK, so I've been working on computers for years and have never seen anything like this... neither have any of my colleagues. I am trying to help someone out who has some issues with flash player. Basically flash player is installed on the computer, but whenever I visit youtube or another site with flash, it just shows a black square. I have run every virus scan I can think of (MBAM, Spybot, SAS, McAfee Stinger, HiJack This!, Norton Power Eraser, Kaspersky TDSS killer, Combofix, Avira) and all of them come up with nothing. I have tried reinstalling flash at least 5 times, removing every program that has even a remote possibly of conflicting (using Revo to be sure they are completely removed). I have disabled every startup program on the computer, updated every driver, rolled back, (then updated) every driver, and verified that all hardware is functional. I have also disabled their AV and firewall.
Nothing works; except for when the computer is in safe mode. Then everything works fine.
Can anyone think of anything I am missing?
I did try clearing cache and cookies as well. I also used multiple browsers (including Chrome; which has flash built right into it). I used Firefox portable as well... which should be running separately from any settings in the system.
Also; I did Google the heck out of this one before posting, so no lmgtfy links please... ;)