Misplace in record, like file not in use (6)
I believe the answer is:
closed
'like file not in use' is the definition.
(like an unopened file on a computer)
'misplace in record' is the wordplay.
'misplace' becomes 'lose' (synonyms).
'in' indicates putting letters inside.
'record' becomes 'cd' (type of musical record).
'lose' going into 'cd' is 'CLOSED'.
(Other definitions for closed that I've seen before include "successfully completed" , "Not open or available to all" , "Terminated" , "Concluded or fastened" , "restricted" .)