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Specifies the criteria with which the updates are searched on the server (Windows Update Site or WSUS).
If no criteria criterion is specified, WuInstall searches by default for software (no drivers!) which has not yet been installed. So the default criteria is: IsInstalled=0 and Type='Driver'.
When If an invalid criteria criterion was specified, the search fails and WuInstall exits with code 4.
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Searches only for drivers, which have not yet been installed. Equivalent to the criteria (IsInstalled=0 and Type='Driver').
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Searches for software and drivers, which have not yet been installed. Equivalent to criteria (Type='Software' and IsInstalled=0) or (Type='Driver' and IsInstalled=0)
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Searches for all types of updates, which have not yet been installed. Equivalent to criteria criterion (IsInstalled=0).