Sometimes VitalSigns is unable to gather statistics about Domino servers. You will either get a status of "Not Responding" or "Telnet" (meaning that VitalSigns can ping the port of 1352, but that's all.) In the log files you see a variation of the error message "serverstats.dll not found". There are two possible causes:
1) The Visual C++ runtime is not installed. See https://www.microsoft.com/en-us/download/details.aspx?id=26368
2) The path variable on the monitoring station is not pointing to the location of the Notes client.
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