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For more information, see also the WuInstall HowTos
How to get "Important" updates only?
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Why does WuInstall crash/generate failures during the download or installation of updates?
Are you using the show_progress option? This feature is not recommend for common usage. It might cause under certain circumstances on some machines problems.
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When using Windows XP it might cause problems using the "run as" command together with WuInstall. To prevent this you should use the /quiet and /disableprompt option on the end of your command.
Windows 7 Service Pack 1 installation fails, why?
Do you use the option /quiet when executing WuInstall? The installation of Windows 7 Service Pack 1 with the option /quiet could cause some error. Please try to execute WuInstall without /quiet.
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Then just add the parameters /quiet /disableprompt to your WuInstall call - this should fix the issue.
Also take a look at this faq.
Does WuInstall work with Windows 8 / Server 2012?
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This error usually indicates a connection problem. There is no connection to the WSUS or to the Windows Update Server. Probably, the WSUS - address is just configured incorrectly or there are proxy problems.
See also http://support.microsoft.com/kb/836941/en-us
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For further information about error codes see please Error Codes.
WuInstall PRO Licensing
How is the WuInstall license price calculated?
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