I can't chat using this version in Facebook.Similarly,I can't install the available updates though my mac book meets the general requirements for it.I can't choose the location to be installed.
That is a very old version of Safari! The version for Leopard 10.5.8 is 5.0.6. which works on Facebook.
Safari 5.0.6 for Leopard can be downloaded from here:
What updates (or even upgrades) are you having problems with?
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