adpatch failed with error: "Missing file format id in file"

ERROR
--------------------------------------------
Defaults Feature Enabled = YES.
Non-Interactive Mode = YES.
Num Workers = 4.
Flags = "hidepw".
Options = "novalidate,norevcache,noprereq,hotpatch".
Patch Top = "/slot/ems2962/appmgr/apps/apps_st/appl/patches/3413892/patches/16020972".

AutoPatch error:
Missing file format id in file:

/slot/ems2962/appmgr/apps/apps_st/appl/admin/ml0yd213/restart/adpinit.rf9

This version of AutoPatch requires a file format id
on the first line of the file.
--------------------------------------------


Solution
1. Rename the file adainit.rf9
cd /slot/ems2962/appmgr/apps/apps_st/appl/admin/ml0yd213/restart
mv adpinit.rf9 adpinit.rf9_bk

2. Start the failing Patch again.

Reference
adpatch fails after being restarted: "Unable to read file format id from file adainit.rf9" (Doc ID 402751.1)

AutoPatch Error: Missing File Format ID In File applcust.txt (Doc ID 1227113.1)