OnCommand Balance discovery collection disabled for some servers

[IGORSTOJNOV]

Hello,

I'm using Balance 4.1.1.1 for monitoring our vSphere environment.

Recently, when I looked up some virtual servers - it turned out there's no information in Summary and Data Topology tabs.

When I checked the server discovery settings, it turned out that some servers have their discovery and statistics collection DISABLED.

The thing is, I don't remember making any config alterations. (?)

And when I click on Disabled link I get the following info and subsequent Rediscovery fails with the following error: 

Can someone tell me what might be the cause of this situation? I already tried vCenter rediscovery, didn't help.

Also, how do I enable data collection for these virtual machines again? 

Thanks!