If you are using a windows 2003 server, apache, this error pops out from the ssl.log files

An operation was attempted on something that is not a socket. : Child
4800: Encountered too many errors accepting client connections. Possible causes:
dynamic address renewal, or incompatible VPN or firewall software. Try using the
Win32DisableAcceptEx directive.


Switch Plesk Control Panel to IIS.

Run the following from the command prompt:

"%plesk_bin%\reconfigurator.exe" --switch-plesk-web-server --new-provider=iis

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