Hardware issues. The MATRIX chip elf launcher does that when it can't access the DEV9 device(whatever is connected to the expansion port connector) properly.
Have your console serviced by a technician or get another unit. Make sure you test the network adapter and harddrive on another console before, to make sure if it's not the harddrive or the network adapter the source of your problem.
If the console had the "golden disc syndrome, the fault that causes it (short circuit on IOP address lines) will also prevent the expansion bay from working properly.
SCPH-10000_GH-001 SCPH-15000_GH-003 SCPH-18000_GH-008 SCPH-30001_GH-005 SCPH-30000_GH-016(V4) SCPH-30001_GH-010(V4)
2xSCPH-10190, 2xSCPH-10350, 2xSCPH-10280
"**** j0 hackers!"
-Sjeep (As seen on TOXIC OS ELF...)