SysLog for External USB Optical Drive Booting Failure - HRev51877 Hybrid 32-bits.
Notebook is Aspire One 721-3922 with Windows 7 and three partitions on hard drive.
External USB Optical Drive is Sony DRX-S50U.

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Welcome to the Haiku boot loader!
number of drives: 1
add_partitions_for(0x00105338, mountFS = no)
add_partitions_for(fd = 0, mountFS = no)
0x00105560 Partition::Partition
0x00105560 Partition::Scan()
boot partition offset: 0
0x00105660 Partition::_Mount check for file_system : TAR filesystem
PackageVolumeInfo::SetTo()
PackageVolumeInfo::SetTo():failed to open package directory:No such file or directory
add_partitions_for(0x001053f8, mountFS = yes)
add_partitions_for(fd = 1, mountFS = yes)
0x00106c20 Partition::Partition
0x00106c20 Partition::Scan()
Check for partitioning_system: GUID Partition Map
Check for partitioning_system: Intel Partition Map priority : 810
Check for partitioning_system: Intel Extended Partition

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Parent Partition 0x00106c20
Add child partitions:
Child 0x00106d98
Child 0x00106e60
Child 0x00106f38

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Each child partition is scanned for partitioning system then for file system (BFS, then FAT32, then TAR)

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0x00106d98 Partition::~Partition
0x00106e60 Partition::~Partition
0x00106f38 Partition::~Partition
0x00106c20 Partition::~Partition

The above are the last entries from the boot loader.

Allow to continue booting.

Splash screen icons light up -> Atom, Disk mangifier, Plug-in card, and Boot disk.

A number of seeks are heard from the optical drive.

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PANIC: did not find any boot partitions!
Welcome to Kernel Debugging Land...
Thread 15 "main2" running on CPU0
Kernel stack: 0x82423000 to 0x82427000

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>A total of 10 frames - from 0 to 9 -> showing from deepest up to the panic() call:
>9: common_thread_entry_FPV() + 0x3b
>8: main2_FPV(0) + 0xad
>7: VFS_mount_boot_filesystem() + 0x60
>6: panic() + 0x3a