The intel-macs come pre-loaded with intel-native plugins for macromedia flash content - but it is possible for these to be over-written with the wrong plugins - after which Flash content will not play in Safari.
Here's a couple of simple-ish ways to restore the files; hopefully explained in simple terms.
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The correct files can be found on your original OS X Tiger installation disk & can be extracted using an application called Pacifist from
http://www.charlessoft.com/ . Follow the instructions in the first post in
this thread.
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There's a thread
here that has a link to a zipfile of what is contained on your install disk
http://formymac.com/MR/plugins.zip
If you are
rightly cautious about downloading this file - check out the thread & view the
public profile of the guy who put it up for grabs.
Then instead of clicking on the link I gave - ctrl-click it & choose 'download linked file' . Then click the downloaded file
once & press Apple-I for the 'get info' window & make sure that 'Kind' does show as a zip archive.
If you're happy to use this file - download it ( 3.5MB) & open it ... it should unzip & create a folder named "internet plug-ins"
Open this folder & locate the files named
Flash Player.plugin & NP-PPC-Dir-Shockwave
Select both files ( click one, then Apple-click the other so they're both highlighted ) Then ctrl-click on one of them & choose "copy 2 items".
From the Finder menu, choose Go - Go to folder & paste
/Library/Internet Plug-ins/ into the address box & click the Go button.
Ctrl-click on an empty space inside the folder & choose 'paste items' . Choose 'replace' if you get a dialogue box saying " a file with the name xxx already exists..."
Quit Safari, open it again & Flash should work again. You can check that the plug-ins were recognised by going to Safari-Help-Installed Plug ins .
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