As requested with verify switched on, still not able to be read on three other DVD readers, says unreadable disk.
I 16:28:42 Operation Started!
I 16:28:42 Source File: C:\Downloads\backup biz
I 16:28:42 Source File Sectors: 3,825,924 (MODE1/2048)
I 16:28:42 Source File Size: 7,835,492,352 bytes
I 16:28:42 Source File Volume Identifier: backup2008
I 16:28:42 Source File Volume Set Identifier: 34672923
I 16:28:42 Source File Implementation Identifier: backup.iso
I 16:28:42 Source File File System(s): ISO9660, UDF (1.02)
I 16:28:42 Destination Device: [1:1:0] HL-DT-ST DVDRAM GSA-H42N RL01 (D:) (ATA)
I 16:28:42 Destination Media Type: DVD+R DL (Disc ID: RICOHJPN-D01-67) (Speeds: 2.4x, 4x, 6x, 8x)
I 16:28:42 Destination Media Sectors: 4,173,824
I 16:28:42 Write Mode: DVD
I 16:28:42 Write Type: DAO
I 16:28:42 Write Speed: 4x
I 16:28:42 Link Size: Auto
I 16:28:42 Test Mode: No
I 16:28:42 OPC: No
I 16:28:42 BURN-Proof: Enabled
I 16:28:42 Book Type Setting: DVD-ROM
I 16:28:42 Optimal L0 Data Zone Capacity: 1,913,760
I 16:28:42 Optimal L0 Data Zone Method: Copied From Original Disc
I 16:29:11 Filling Buffer... (20 MB)
I 16:29:12 Writing LeadIn...
I 16:29:28 Writing Session 1 of 1... (1 Track, LBA: 0 - 3825923)
I 16:29:28 Writing Track 1 of 1... (MODE1/2048, LBA: 0 - 3825923)
I 16:29:28 Writing Layer 0... (LBA: 0 - 1913759)
I 16:41:15 Writing Layer 1... (LBA: 1913760 - 3825923)
I 16:53:02 Synchronising Cache...
I 16:53:03 Closing Track...
I 16:53:18 Finalising Disc...
I 16:54:24 Image MD5: 83cd5ac7a3d56adfa43d880fbfb12ab7
I 16:54:24 Operation Successfully Completed! - Duration: 00:25:42
I 16:54:24 Average Write Rate: 5,415 KB/s (3.9x) - Maximum Write Rate: 5,566 KB/s (4.0x)
I 16:54:24 Cycling Tray before Verify...
W 16:54:34 Waiting for device to become ready...
I 16:55:02 Device Ready!
I 16:55:04 Operation Started!
I 16:55:04 Source Device: [1:1:0] HL-DT-ST DVDRAM GSA-H42N RL01 (D:) (ATA)
I 16:55:04 Source Media Type: DVD+R DL (Book Type: DVD-ROM) (Disc ID: RICOHJPN-D01-67) (Speeds: 2.4x, 4x, 6x, 8x)
I 16:55:04 Image File: C:\Downloads\backup biz
I 16:55:04 Image File Sectors: 3,825,924 (MODE1/2048)
I 16:55:04 Image File Size: 7,835,492,352 bytes
I 16:55:04 Image File Volume Identifier: backup2008
I 16:55:04 Image File Volume Set Identifier: 34672923
I 16:55:04 Image File Implementation Identifier: backup.iso
I 16:55:04 Image File File System(s): ISO9660, UDF (1.02)
I 16:55:04 Read Speed (Data/Audio): MAX / MAX
I 16:55:04 Verifying Session 1 of 1... (1 Track, LBA: 0 - 3825923)
I 16:55:04 Verifying Track 1 of 1... (MODE1/2048, LBA: 0 - 3825923)
I 16:55:04 Verifying Layer 0... (LBA: 0 - 1913759)
I 17:03:24 Verifying Layer 1... (LBA: 1913760 - 3825923)
I 17:09:47 Device MD5: 83cd5ac7a3d56adfa43d880fbfb12ab7
I 17:09:47 Device (Padded) MD5: d0bec20aefc4d33e7a185ab825be06ac
I 17:09:47 Image MD5: 83cd5ac7a3d56adfa43d880fbfb12ab7
I 17:09:54 Operation Successfully Completed! - Duration: 00:14:43
I 17:09:54 Average Verify Rate: 8,665 KB/s (6.3x) - Maximum Verify Rate: 11,132 KB/s (8.0x)