DVD burns ok mounted after burn, once ejected will not mount anymore

[jett_borja]

Im using Toast 7.0.1 as well as Burn in the finder i don't have any problem in burning and in fact after it is finished it will mount on the desktop but once i ejected, it will not mount anymore, i try to use to my friends mac, he can read all my recorded DVD's. But if i used Original DVD (not burned) it is easily mounted. I try to search any forums but didn't get any solution, maybe i am in the right place now to pix this problem. Thanks in advance guys!!!

Here is my system prefs>>>

MAC Os x 10.4.3
Dual 2 Ghz G5
512 mb ram

ATA Bus:
PIONEER DVD-RW DVR-107D:
Model: PIONEER DVD-RW DVR-107D
Revision: A707
Detachable Drive: No
Protocol: ATAPI
Unit Number: 0
Socket Type: Internal

PIONEER DVD-RW DVR-107D:
Firmware Revision: A707
Interconnect: ATAPI
Burn Support: Yes (Vendor Supported)
Profile Path: /Library/DiscRecording/DeviceProfiles/PatchBurn-pioneerdvdrwdvr107d.drprofile
Cache: 2000 KB
Reads DVD: Yes
CD-Write: -R, -RW
DVD-Write: -R, -RW, +R, +RW
Burn Underrun Protection CD: Yes
Burn Underrun Protection DVD: Yes
Write Strategies: CD-TAO, CD-SAO, CD-Raw, DVD-DAO
Media: No