How to get plc to work properly after manually deleting some archived soamdb files?

Question

After user manually deleted some archived soamdb files under $EGO_CONFDIR/../../soam/work/history/ certain messages were repeated in the symtaskhistloader log (see below). Although plc is in START state, it does not work properly. 2017-10-02 10:15:00.957 WARN com.platform.perf.dataloader.soam.FDataLoader.queryHisFile(FDataLoader.java:473) The file \\zzzz-zzzz\GAAS_PRD\kernel\conf\..\..\soam\work\history\00000\12_\__\DEV_SHARED_PRICINGSERVICES_task.soamdb.2017_6_19_9_53_21_0 does not exist. Check your history file for the correct file name. 2017-10-02 10:15:00.957 ERROR com.platform.perf.dataloader.DefaultDataLoader.execute(DefaultDataLoader.java:354) An error occurred during the data read process. java.lang.NullPointerException         at com.platform.perf.dataloader.soam.FDataLoader.readRecords(FDataLoader.java:275)         at com.platform.perf.dataloader.soam.FileLoaderMgr.readRecords(FileLoaderMgr.java:327)         at com.platform.perf.dataloader.soam.LoaderDecorator.readRecords(LoaderDecorator.java:74)         at com.platform.perf.dataloader.soam.TaskFDataReaderMgr.readRecords(TaskFDataReaderMgr.java:46)         at com.platform.perf.dataloader.soam.TaskFDataReaderMgr$$EnhancerByCGLIB$$28b2fc8.CGLIB$readRecords$3()         at com.platform.perf.dataloader.soam.TaskFDataReaderMgr$$EnhancerByCGLIB$$28b2fc8$$FastClassByCGLIB$$7bad7d75.invoke()         at net.sf.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:167)         at com.platform.perf.dataloader.ReaderFactory$EnhancerUtil.intercept(ReaderFactory.java:120)         at com.platform.perf.dataloader.soam.TaskFDataReaderMgr$$EnhancerByCGLIB$$28b2fc8.readRecords()         at com.platform.perf.dataloader.DefaultDataLoader.execute(DefaultDataLoader.java:348)         at com.platform.perf.dataloader.DataLoaderJob.execute(DataLoaderJob.java:102)         at org.quartz.core.JobRunShell.run(JobRunShell.java:202)         at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:525) 2017-10-02 10:15:00.957 INFO com.platform.perf.dataloader.DefaultDataLoader.execute(DefaultDataLoader.java:531) Read 0 records.