My iPod says do not disconnect but not recognized by computer

My iPod works fine until I connect it to the computer, but then it says "do not disconnect" and will not be recognized by the computer. It is not recognized in iTunes either.

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2889612:0crwdne2889612:0 0
crwdns2934285:0crwdne2934285:0