How to remove Quarantine from file permissions in OS X

Question

I downloaded a .pem file and my Mac OS X (10.8.2) added an @ sign at the end of the file permissions. This is causing file permission issues.

I can't seem to remove the quarantine flag. I even tried the command

xattr -d <filename>.pem 

but that didn't work.

Answer 1

First, use ls -l@ to see what extended attributes are attached to the file. Normally, a downloaded file will have xattrs named "com.apple.quarantine" and maybe "com.apple.metadata:kMDItemWhereFroms". To remove them, you can delete them individually with e.g. xattr -d com.apple.quarantine filename.pem, or clear all xattrs with xattr -c filename.pem