SQL Server FILESTREAM Won't Enable access for I/O

I have a SQL Server 2012 64 bit version running on a Windows Server 2008 R2 64 bit version. I wanted to enable the FILESTREAM feature.

In the FILESTREAM tab of the properties of SQL Server in config manager, I can enable the option for Transact-SQL access but when I try to enable the option for file I/O access, I get the following error message: There was an unknown error applying the FILESTREAM settings. Check the parameters are valid. (0x80070001)

Then on the bottom of the page there is a message that says: A previous FILESTREAM configuration attempt was incomplete. FILESTREAM may be in an inconsistent state until re-configured.

What exactly does this mean? How can I re-configure it? Any help would be highly appreciated.