Problem burning

i have just started having a problem burning to dvd. i was using v3 when the problem started, so i went back and tried the previous version but still had the same result.
20/04/2008 18:08:23 info Media removed. Burning layer not ready to write
20/04/2008 16:30:01 error Write error at 1824160 (16) - Code 06 29 00 [Unit attention, Power On or Bus device reset occured]
20/04/2008 15:49:35 info Lead-in burning time (mS) 1
20/04/2008 15:49:17 info Write started 2250528 sectors to write
20/04/2008 15:49:17 info Init success: DVD-R SAO
20/04/2008 15:49:17 info Writing speed requested x4.0, effective x4.0
20/04/2008 15:49:17 info Available write speed: 8x, 4x, 2.4x
20/04/2008 15:49:17 info Media ID: INFODISC-R20
20/04/2008 15:49:17 info Media type: DVD-R
20/04/2008 15:49:17 error Log file can’t be saved on disk. Please select a different location - Current “”
hope this makes sense to someone. many thanks in advance gary