This happens occasionally with random files, and is fixed on restart... Chkdsk shows no errors.
Here is an example:
Using iTunes, it plays through my library fine... Then I decide to listen to some artist, and all the songs come up with the '!' icon, so I try to locate the song and it will say my iTunes/Media/Music folder is 'Unreadable or Corrupt' or something along those lines. And suggest that I run chkdsk.
However, the folder clearly isn't unreadable or corrupt because the rest of my music is also in the folder. And it functions fine after a restart, and as said, chkdsk shows no errors.
Any ideas? The HDD is about 3 years old now. It started acting strange when it was in my old PC, now I have a new one and just using this as a Data drive with windows and programs on my SSD. But it's quite irritating when say I want to listen to a certain artist, or open a certain word document and have to restart my computer to do so!