Oracle Error Message
ORA-15028: ASM file ‘string’ not dropped; currently being accessed
Reason for the Error
An attempt was made to drop an ASM file, but the file was being accessed by one or more clients and therefore could not be dropped.
Solution
Stop all clients that are using this file and retry the drop command. Query the V$ASM_CLIENT fixed view in an ASM instance or use ASMCMD LSOF to list active clients.