DVR-108: 'Internal Target Failure'/'Invalid Address for Write' errors?

Nero and Alcohol 120 % both give me these errors (Internal Target Failure in Nero,
Invalid Address for Write in Alcohol 120 %) before starting the burning of all discs in my Pioneer DVR-108 drive. This happens even before the drive goes to spin up the disc. I can’t brun anything in the drive. Reading of CDs is fine, but DVD-R reading is very hit-and-miss.

What’s happening here and how can I remedy the problem?
Thanks very much…

PS: I’ve tried different versions of the software and I still get that error.

PPS: Here’s Alcohol 120%'s recent burning log:

####################### Dumping/Recording Progress Log #######################
********* Time stamp of this log file: 2006-04-16 20:30:10 *********
20:30:10 Processor info: AMD Sempron™ (1266MHz)
20:30:10 Memory Available to Windows: 458’224 KB
20:30:10 Memory Buffer size: 128 MB
Recording Options: Use Overburning technology
20:30:11 Image file loading: S:\CD & DVD Images\SEGA\Dreamcast\Under Defeat (NTSC) (JP)\Under Defeat (NTSC) (JP).cdi
20:30:11 Source Info: Session: 2, Track: 2, Length: 642.4 MB / 073:05:43
20:30:14 (D:) PIONEER DVD-RW DVR-108(1:0): Recording Method/Speed
20:30:15 Recording - RAW DAO - 32X (4800 KB/Sec)
(D:) PIONEER DVD-RW DVR-108(1:0): RAW DAO Write Mode - RAW-PW(96)
20:30:15 (D:) PIONEER DVD-RW DVR-108(1:0): BURN-Free activated
20:30:36 (D:) PIONEER DVD-RW DVR-108(1:0) - [Write Lead-In area ERROR]: -11849 - -151
S:KEY - 05/21/02 - “Invalid Address For Write”
20:30:36 (D:) PIONEER DVD-RW DVR-108(1:0): Recording failed!
20:30:36 Error message: [05/21/02] - Invalid Address For Write
20:30:36 (D:) PIONEER DVD-RW DVR-108(1:0): Recording failed!
20:30:36 Image file loading aborted!
20:30:40 Something is wrong with the recording procedure! Please check the log file and report any errors to Technical Support.
##############################################################################

What has that to do with DVD burning??

I get the error on both CD & DVD burning.

The same error?

Then try the burner in another computer.