I have a PowerBook G4 and when I open Safari oir try to do OS updates it crashes immediatly with the same error

Exception:Exec_bad_Access (0x0001)
Codes:Kern_Protection_failure (0x0002) at 0x00000000

There is a massive log after this which i had posted here bfore but my post has disapeared.
So Far I have taken both memory sticks out, run a full memtestosx, cloned the hdd to an external hard drive and booted off this, repaired the permissions and disk, but still have the same problem can someone help me please, I am just about at the point of reloading from scratch ?