what causes input/output error?
 

I get an input/output error for a particular file when trying to copy. Is it possible to say what might be causing that?

By the way, no big deal but for some reason I couldn't log back into the forum, I tried resetting my password but it wouldn't accept it.

In general, it's because the file is on a damaged section of the drive. The Troubleshooting section of the User's Guide goes into some detail...