What does error code 77 mean?

[Talidorn]

(Return code of 77 for service 'WebService xxx.xxxx.xxx' on host 'xxx01' was out of bounds)
File name: 'Microsoft.Web.Administration, Version=7.0.0.0, Culture=neutral, PublicKeyToken=16charstring'
at MonitoringPluginsForWindows.check_iis.CheckAllSites(Int32 returncode, Boolean do_perfcounter_sites, Boolean do_singluar_check, String expected_state)
at MonitoringPluginsForWindows.check_iis.Main(String[] args)

WRN: Assembly binding logging is turned OFF.
To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.
Note: There is some performance penalty associated with assembly bind failure logging.

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