Hi folks, I found some threads with cases similar to mine, but not exactly... so I figure to post a new one here. My iMac is set up to bootcamp Windows 7. Recently the Windows partition is full so yesterday I reduced the OS X partition (using Disk Utility), and extended the Windows partition (using MiniTool Partition Wizard free). Everything went well...until I boot to OS X. Now in Startup Disk, it can't find my bootcamp disk. Bootcamp disk is not shown in Finder as well. However, my bootcamp does show in Startup Manager (hitting "option" key while starting the Mac), and I can boot to Windows with no problem. And in Windows environment, everything is intact, it shows the reduced OS X partition and extended Windows partition. The report from Partition Inspector shows: Code: *** Report for internal hard disk *** Current GPT partition table: # Start LBA End LBA Type 1 40 409639 EFI System (FAT) 2 409640 879315887 Mac OS X HFS+ 3 879315888 880585423 Mac OS X Boot 4 1271212032 1953523711 Basic Data Current MBR partition table: # A Start LBA End LBA Type 1 1 409639 ee EFI Protective 2 409640 879315887 af Mac OS X HFS+ 3 879315888 880585423 ab Mac OS X Boot 4 * 880586752 1953523711 07 NTFS/HPFS MBR contents: Boot Code: Unknown, but bootable Partition at LBA 40: Boot Code: None (Non-system disk message) File System: FAT32 Listed in GPT as partition 1, type EFI System (FAT) Partition at LBA 409640: Boot Code: None File System: HFS Extended (HFS+) Listed in GPT as partition 2, type Mac OS X HFS+ Listed in MBR as partition 2, type af Mac OS X HFS+ Partition at LBA 879315888: Boot Code: None File System: HFS Extended (HFS+) Listed in GPT as partition 3, type Mac OS X Boot Listed in MBR as partition 3, type ab Mac OS X Boot Partition at LBA 1271212032: Boot Code: None File System: Unknown Listed in GPT as partition 4, type Basic Data Partition at LBA 880586752: Boot Code: Windows BOOTMGR (Vista) File System: NTFS Listed in MBR as partition 4, type 07 NTFS/HPFS, active The result from sudo gpt -r -vv show /dev/rdisk0: Code: pt show: /dev/rdisk0: mediasize=1000204886016; sectorsize=512; blocks=1953525168 gpt show: /dev/rdisk0: Suspicious MBR at sector 0 gpt show: /dev/rdisk0: Pri GPT at sector 1 gpt show: /dev/rdisk0: Sec GPT at sector 1953525167 start size index contents 0 1 MBR 1 1 Pri GPT header 2 32 Pri GPT table 34 6 40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B 409640 878906248 2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC 879315888 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC 880585424 1328 880586752 390625280 4 1271212032 682311680 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7 1953523712 1423 1953525135 32 Sec GPT table 1953525167 1 Sec GPT header By going through different articles related to similar problems, I suspect my GPT record is not correct, but I am not sure (since in many other cases, it is the MBR that causes the issue) Can anyone help me to look into it and give me some input? I am also unsure how to fix the GPT if it is indeed the cause of the issue. Thank you very much.