UIS GID and sticky bit problem

Question

Not sure the best place to post this, could not find a forum that really matched what I am asking.
My Chronosync is having problems with not being able to backup certain files. (cover.jpg)
I seem to have traced it to files with what I think is a Sticky bit....but I thought a file with a sticky bit was shown with a t as in:
-rwxrwxrwxt
but the problem files are shown :
-rwxrwxrwx@
It is a file that I have moved from one user to another via the Drop box...so i know that causes issues with UID GID and Sticky bits etc
How in terminal do i correct the file permissions to:
-rwxrwxrwx
OK I could just re download the file or copy it from the other user another way...but I am still interested in this "@" attached to the permission string and how to change it.
have tried various combinations of chown and chmod but cant get any change...
I have seen some references to it being a indicator to the OS that it is a file downloaded from the internet...but how to remove this ?
sh-3.2# ls -l
total 1986808
-rwxrwxrwx@ 1 bonair staff 6148 3 May 13:45 .DS_Store
-rwxrwxrwx 1 bonair staff 174187271 3 May 14:11 01 - Bastity Chelt.flac
-rwxrwxrwx 1 bonair staff 144769872 3 May 14:11 02 - Jersey.flac
-rwxrwxrwx 1 bonair staff 179664537 3 May 14:11 03 - The Football Match.flac
-rwxrwxrwx 1 bonair staff 133005983 3 May 14:11 04 - America.flac
-rwxrwxrwx 1 bonair staff 38122932 3 May 14:11 05 - Zits.flac
-rwxrwxrwx 1 bonair staff 54626233 3 May 14:11 06 - Number Plates.flac
-rwxrwxrwx 1 bonair staff 129378885 3 May 14:11 07 - The Bus Trip.flac
-rwxrwxrwx 1 bonair staff 57536059 3 May 14:11 08 - Car Insurance.flac
-rwxrwxrwx 1 bonair staff 104705018 3 May 14:11 09 - Magic Roundabout.flac
-rwxrwxrwx@ 1 bonair staff 471848 3 May 12:04 cover copy.jpg
-rwxrwxrwx@ 1 bonair staff 471848 3 May 12:04 cover.jpg
sh-3.2#

Answer 1

I already gave you the Unix command to tell you what the @ indicates
ls -aleO@ # lowercase l, lowercase e, capital O, and at sign
Why not use it?
I also suggested what each extended attribute might be, but without output from the above ls -leO@ I can only guess.
Here are the relevant parts of "man ls"
-a Include directory entries whose names begin with a dot (.).
-l (The lowercase letter ``ell''.) List in long format. (See
below.) If the output is to a terminal, a total sum for all the
file sizes is output on a line before the long listing.
-e Print the Access Control List (ACL) associated with the file, if
present. Also see "man chmod".
-O Include the file flags in a long (-l) output.
Also see "man chflags".
-@ Display extended attribute keys and sizes.
There is no man page for extended attributes, however, there is a minimal amount of usage information built into the command:
xattr --help
usage: xattr [-l] file [file ...]
xattr -p [-l] attr_name file [file ...]
xattr -w attr_name attr_value file [file ...]
xattr -d attr_name file [file ...]
The first form lists the names of all xattrs on the given file(s).
The second form (-p) prints the value of the xattr attr_name.
The third form (-w) sets the value of the xattr attr_name to attr_value.
The fourth form (-d) deletes the xattr attr_name.
options:
-h: print this help
-l: print long format (attr_name: attr_value)