Files Greyed out in Finder - Potential extended attributes issue?
Solution 1:
This worked, but after external disk (NTFS) eject the problem was back
xattr -d com.apple.FinderInfo fileToUpdate
(or for all files in a folder xattr -d com.apple.FinderInfo *)
This worked after eject/re-mount
xattr -wx com.apple.FinderInfo
0000000000000000001000000000000000000000000000000000000000000000 fileToUpdate
Notes from man xattr:
xattr -w [-rsx] attr_name attr_value file ...
xattr -x Force the attribute value to be displayed in the hexadecimal representation.