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Hi Because of some issues actually we don't like to upgrade to the newest PRTG Version. But our esxi envoironement is now on Version 7 and i get the error PRTG "The underlying connection was closed: An unexpected error occurred on a send." Any chance to get it back working without update?

error-messages esxi prtg

Created on Jul 19, 2018 11:24:27 AM

3 Replies



Hi there,

Thank you very much for the contact.

To which sensor type do you refer precisely? Please upload a screenshot the sensor's Overview tab for further analysis.

I'm not quite sure yet but I could imagine that an update of PRTG might help to solve this issue, as our developers worked on the VMware sensors just recently. What issues do you encounter and what keeps you struggling in regards to the update?

Best regards,

Created on Jul 20, 2018 7:43:26 AM by  Sebastian Kniege [Paessler Support]



Hi Sebastian,


Hope the link to the screenshot on my OneDrive work... It refer to all VMware sensors... i Setup a test prtg Server with the newest Version and there is everything ok..

we struggled on our last attempt with the new webgui. we Need some testing also with some rest sensor first before updating..

Created on Jul 23, 2018 6:25:26 AM

Last change on Jul 23, 2018 7:19:12 AM by  Sebastian Kniege [Paessler Support]



Hi dawed,

Thank you very much for your reply. According to the screenshot it appears as the used PRTG version is slightly older.

Please note ESX 7 requires another version of the sensor which is compiled with another .NET version. This sensor is part of the latest versions of PRTG but can't be migrated to your older version, I'm afraid.

Please update PRTG to solve this issue. If you have particular questions or issues with the facelift, don't hesitate to contact use directly via email at [email protected].

Best regards,

Created on Jul 23, 2018 7:52:01 AM by  Sebastian Kniege [Paessler Support]

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