03/21/2017 17:52:22 ARC HAS REQUESTED 4 SESSIONS, TASM HAS GRANTED IT 4 SESSIONS
03/21/2017 17:52:22 UTILITY EVENT NUMBER - 250
03/21/2017 17:52:22 LOGGED ON 4 SESSIONS
03/21/2017 17:52:22 STARTING TO RESTORE DATABASE "DBC"
03/21/2017 17:52:49 *** Failure 3596:Invalid restore of database DBC.
03/21/2017 17:52:51 LOGGED OFF 7 SESSIONS
03/21/2017 17:52:51 ARCMAIN TERMINATED WITH SEVERITY 12
you shoud check out the Archive/Recovery utility reference documentation for procedures to restore database DBC.
You'll start with a sysint followed by Dip .
The link to documentation is found at the bottom of community.