This type of error message is seen when a file or directory that was opened by an NFS client is removed, renamed, or replaced.
To fix this problem, the NFS file handles must be renegotiated. Try one of these on the client machine:
a) Unmount and remount the file system, may need to use the -O (overlay option) of mount.
From the man pages: -O Overlay mount. Allow the file system to be mounted over an existing mount point, making the underlying file system inaccessible. If a mount is attempted on a pre-existing mount point without setting this flag, the mount will fail,
producing the error "device busy".
b) Kill or restart the process trying to use the nonexistent files.
c) Create another mount point and access the files from the new mount point.
d) Run: /etc/init.d/nfs.client stop; /etc/init.d/nfs.client start
e) Reboot the client having problems.