Currently Being ModeratedApr 4, 2013 11:36 AM (in response to SHAUNUXBRIDGE)
Hello, it's generally one of two thinks that cause this, but it is a bad download.
Try Ethernet instead of Airport if possible.
Disk can be corrupted...
Safe Boot, (holding Shift key down at bootup), run Disk Utility in Applications>Utilities, then highlight your drive, click on Repair Permissions, reboot when it completes.
(Safe boot may stay on the gray radian for a long time, let it go, it's trying to repair the Hard Drive.)
Try getting it direct instead of SWUPDate...
Repair Permissions afterwords, reboot.
1058 Combo Update, 10.5.8...