I have a dual boot of Mac/Windows 7 and they are both installed on an SSD. All my user files were on a separate hard drive with 3 partitions and 150gb of free space. The 3 partitions were HFS and 2 exFats. The HFS included my Mac user files and the fats just random files.
I was installing a game for windows and the 2 exFats were before formatted exFat from the Mac side, due to this I couldn't install it from the windows side because it was read only. So I formatted the 150 GB remaining as exFat from the windows side so I could use it. Then windows 7 converts the drive to a dynamic/simple format after I attempt to create the volume.
I tried rebooting into Mac and it said it couldn't access my user files on the separate drive and therefore couldn't log me in as that user. I then went to single user mode and tried fsck_exfat but that returned:
Main Boot Region is invalid &
Invalid jump or signature. In an attempt to fix this I ran MiniTool Partition Wizard and converted the dynamic drive to basic. This appeared that it undid what windows did, but the Mac side is showing the same errors.