Removing the bootcamp partition is one way but way too draconic for the issue... Just follow these steps instead...
1. go into your windows (full boot)
2. in windows > start menu > cmd > righclick > open as administrator
3. type in: chkdsk /f and press enter
it will say it needs a reboot because disk is in use
4. reboot (into windows)
5. let the chkdsk operation finish and reboot to mac after that
6. et voila... problem solved (in mac)...