Greyed out/inaccessible files on File Sharing server on Mac OS My company has a single file sharing Mac Pro computer that every user connects to. Occasionally a user will drop a file in a folder for another user to access, but the the files will be greyed out and are inaccessible to the other user, while a different user can see and access it as normal. Sometimes dropping a file will cause a user to just have spinning ball and will not drop.

It has worked well enough for a few months now, but this problems has been becoming more frequent.

Everyone, which is about 20 users all with iMac or Mac pros, connects to the file sharing Mac Pro using the same registered username and password. I have everyone connected via SMB. The file sharing Mac Pro has a Drobo via USB that hosts all the files. All the permissions are set to write and read for everyone.

Any idea on how to fix this? Do I have this setup correctly?
Everyone, which is about 20 users all with iMac or Mac pros, connects
  to the file sharing Mac Pro using the same registered username and
  password...All the permissions are set to write and read for
  everyone.


Emphasis Mine

This one paragraph sums up the issue you are having; you do not have this setup correctly at all.  What this sounds like is that even though everyone has read/right priviliges, the file gets locked so that only one SMB client can access it at a time.  When two clients access it - even with the same credentials, which client has the correct changes?  SMB solves this for you - the one that got there first.

What you should have is a unique user account for each person that needs to access the file share/server.  If you want to maintain a single login for your users across all servers, look at implementing a directory server of some sort.  I prefer Active Directory as I work in mixed environments; second in line is LDAP.