Hi,
I have a Windows 7 NTFS formatted external usb Drive (WD Passport brand hdd with 1tb), I plugged it into a Retina Macbook pro (rMBP 2015), it was readable but not writable. I proceded to install a trial of the Paragon NTFS for mac 14 and it enabled the HDD to be editable. That worked great until I ejected and plugged the drive back into the windows 7 desktop PC which no longer reads the drive, it recognizes that its a WD passport but it doesn't show in the explorer. After a minute or two of the drive relentlessly spinning, windows says it needs to be formatted. I can't eject it so I have to turn off windows to unplug it. When I hook it to the macbook it works normally.

What's going on? how do I fix this problem? I can't re-format the drive because it's full and I don't have space to unload it on the mac. I have space on the windows PC ...but I can no longer use it there.