How to set V-ray Swarm automatically start?

Hello guys,
In our Studio there are several PCs installed VFR 4.3 and V-Ray swarm 1.4.4, some can automatically start V-Ray swarm, when computer stars up, even not login. But on some PCs we need start V-Ray swarm(ad-hoc), then it works. How can I configure them?
BTW, what is the different between V-Ray swarm(ad-hoc) and V-Ray swarm(start service)?

Hello @IFS_JRN ,

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