and trying to implement the same in SharePoint server 2016 and initially got this error.
Item not crawled due to one of the following reasons: Preventive crawl rule; Specified content source hops/depth exceeded; URL has query string parameter; Required protocol handler not found; Preventive robots directive. ( This item was deleted because it was excluded by a crawl rule. )
Then I could able to narrow down to the point that Required protocol handler not found;
After checking in Registry editor (HKEY_LOCAL_MACHINE-->Microsoft-->Office Server-->16.0 -->Search--> ProtocolHandlers )
found that the same Protocol handler is not available and then I copied the same which was found in (HKEY_LOCAL_MACHINE-->Microsoft-->Office Server-->15.0 -->Search--> ProtocolHandlers ) and modified the value to OSearch16.ConnectorProtocolHandler.1 from earlier OSearch15.ConnectorProtocolHandler.1 which was found in 15.0 version and then restarted the search service.
Even then I full crawled. Got the below error.
Error while crawling LOB contents. ( Error caused by exception: Microsoft.SharePoint.BusinessData.Parser.PackageFormatException The LobSystem with Name 'XmlDocumentSystem' and Id '2147483658' has a value in Field 'SystemUtilityType' that is invalid. Error was encountered at or just before Line: '25' and Position: '10'.; SearchID = B2567254-D024-49BB-A03E-D9978ADB55F6 )
Can anyone suggest how to Install and deploy a custom XML indexing connector for SharePoint Server 2016
Or even if you have answer to resolve my issues that would be great!