Please check host server is running properly and check host server is behind firewall and also port 443 is accessible. If the server is behind firewall and if not accessible, then open the port by configuring firewall.
Please check Dot Net Platform is installed in your system. Run the utility available in the bin directory, Check_Dot_Net_version.exe , It will tell you the Dot Net version. If Dot Net platform is not available in the system, download the platform. Please see the software requirements page for downloading the platform.
Yes, 1 server alone can be monitored.
To monitor more server. please visit http://www.manageengine.com/opmanager or send mail to