Make sure box in preferences advanced tab 'show Develop menu in menu bar' is checked as I mentioned before and then do a 10.1 flash download in that order, I think I read flash 10.3 is too high for safari 4.1.3 and Flash 11 is definitely too advanced for Tiger, as well Tiger can not run Firefox or Chrome as a browser, thus the need to get a version of flash that works on your OS Safari version. We both have Tiger installled otherwise known as os 10.4.11, as well I have safari 4.1.3 and flash 10.1, I believe flash 10.3 will not work with OS 10.4.11 (its for a higher version of lion or leopard or something)

I see under system preferences that version 10.3.183.10 is installed, which is the newest version the site gives me. Just says 'missing plug-in', so I guess not. To test if any older versions are still installed on the computer. I can't download newer versions of Chrome or Firefox. I can't update Safari any further with the current OS. I have Mac OS 10.411 which I guess is 64-bit. But I still can't watch videos online and the same message is always displayed 'you need to update Flash, etc.' I go through the installation process and as far as I can tell nothing goes wrong.

A few days ago I was prompted to update Flash Player (youtube videos had suddenly stopped playing on the old version I had) and went ahead and did it.

Updating adobe flash player on mac