Converter job fails immediately as soon as it begin the conversion process.
You may see following in UI as well as in converter log.
reason = "An existing connection was forcibly closed by the remote host", msg = "A general system error occurred: An existing connection was forcibly closed by the remote host"
It’s important to check event viewer log of converter agent on source machine. For e.g. it may crash during conversion process like below.
Log Name: Application Source: Application Error Date: 4/25/2019 11:26:03 AM Event ID: 1000 Task Category: (100) Level: Error Keywords: Classic User: N/A Computer: SourceMachine.domain.local Description: Faulting application name: vmware-converter-a.exe, version: 220.127.116.1123, time stamp: 0x56b9ba76 Faulting module name: MSVCR90.dll, version: 9.0.30729.6871, time stamp: 0x4fee6073 Exception code: 0xc0000005 Fault offset: 0x0006cfae Faulting process id: 0x28c8 Faulting application start time: 0x01d4fb930e2188b3 Faulting application path: C:\Program Files (x86)\VMware\VMware vCenter Converter Standalone Agent\vmware-converter-a.exe Faulting module path: C:\Windows\WinSxS\x86_microsoft.vc90.crt_1fc8b3b9a1e18e3b_9.0.30729.6871_none_50944e7cbcb706e5\MSVCR90.dll Report Id: 94eebc55-6787-11e9-942d-e0db553a662d
If you see same agent crash then uninstall existing converter agents on source physical machine and either install latest version OR let converter server to push/install latest agent before it start conversion process. For my issue, the agent / server was version 6.1.1 build 3533306 was crashing however after installing 6.2.0 Build 846619 of agent & server worked with out any error.
If you see following error is source machine during conversion error then disable SSL encryption as per https://kb.vmware.com/s/article/2020517
Log Name: System Source: Service Control Manager Date: 4/25/2019 1:20:54 PM Event ID: 7034 Task Category: None Level: Error Keywords: Classic User: N/A Computer: SourceMachine.domain.local Description: The VMware vCenter Converter Standalone Agent service terminated unexpectedly. It has done this 1 time(s)