Yacy Can Not Start - Error in SolrCore

Yacy is failing to start with the following error, can anyone tell me how to fix?

E 2020/07/09 16:42:16 STARTUP YaCy cannot start: SolrCore ‘collection1’ is not available due to init failure: Error opening new searcher
org.apache.solr.core.SolrCoreInitializationException: SolrCore ‘collection1’ is not available due to init failure: Error opening new searcher
at org.apache.solr.core.CoreContainer.getCore(CoreContainer.java:1361)
at net.yacy.cora.federate.solr.instance.EmbeddedInstance.(EmbeddedInstance.java:89)
at net.yacy.search.index.Fulltext.connectLocalSolr(Fulltext.java:153)
at net.yacy.search.Switchboard.(Switchboard.java:592)
at net.yacy.yacy.startup(yacy.java:214)
at net.yacy.yacy.main(yacy.java:818)
Caused by: org.apache.solr.common.SolrException: Error opening new searcher
at org.apache.solr.core.SolrCore.(SolrCore.java:977)
at org.apache.solr.core.SolrCore.(SolrCore.java:830)
at org.apache.solr.core.CoreContainer.createFromDescriptor(CoreContainer.java:950)
at org.apache.solr.core.CoreContainer.lambda$load$5(CoreContainer.java:565)
at com.codahale.metrics.InstrumentedExecutorService$InstrumentedCallable.call(InstrumentedExecutorService.java:197)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at org.apache.solr.common.util.ExecutorUtil$MDCAwareThreadPoolExecutor.lambda$execute$0(ExecutorUtil.java:229)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.solr.common.SolrException: Error opening new searcher
at org.apache.solr.core.SolrCore.openNewSearcher(SolrCore.java:2069)
at org.apache.solr.core.SolrCore.getSearcher(SolrCore.java:2189)
at org.apache.solr.core.SolrCore.initSearcher(SolrCore.java:1071)
at org.apache.solr.core.SolrCore.(SolrCore.java:949)
… 9 more
Caused by: org.apache.lucene.index.CorruptIndexException: Unexpected file read error while reading index. (resource=BufferedChecksumIndexInput(MMapIndexInput(path="/opt/yacy/DATA/INDEX/freeworld/SEGMENTS/solr_6_6/collection1/data/index/seg
ments_vcm")))
at org.apache.lucene.index.SegmentInfos.readCommit(SegmentInfos.java:290)
at org.apache.lucene.index.IndexWriter.(IndexWriter.java:930)
at org.apache.solr.update.SolrIndexWriter.(SolrIndexWriter.java:118)
at org.apache.solr.update.SolrIndexWriter.create(SolrIndexWriter.java:93)
at org.apache.solr.update.DefaultSolrCoreState.createMainIndexWriter(DefaultSolrCoreState.java:257)
at org.apache.solr.update.DefaultSolrCoreState.getIndexWriter(DefaultSolrCoreState.java:131)
at org.apache.solr.core.SolrCore.openNewSearcher(SolrCore.java:2030)
… 12 more
Caused by: java.io.EOFException: read past EOF: MMapIndexInput(path="/opt/yacy/DATA/INDEX/freeworld/SEGMENTS/solr_6_6/collection1/data/index/segments_vcm")
at org.apache.lucene.store.ByteBufferIndexInput.readByte(ByteBufferIndexInput.java:75)
at org.apache.lucene.store.BufferedChecksumIndexInput.readByte(BufferedChecksumIndexInput.java:41)
at org.apache.lucene.store.DataInput.readInt(DataInput.java:101)
at org.apache.lucene.index.SegmentInfos.readCommit(SegmentInfos.java:300)
at org.apache.lucene.index.SegmentInfos.readCommit(SegmentInfos.java:288)

I searched for the first line of your error message and at least three other people having the same, or similar problem tracked it down to a file permissions issue.