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/updateSize [lt|gt]:Size(KB|MB|GB) | bt:MinSize(KB|MB|GB)-MaxSize(KB|MB|GB
Use this option to filter for updates which have a download size lower, greater or between the specified size.
/maxTotalSize Size(KB|MB|GB)
This option sets a maximum accumulated size for all updates. WuInstall will iterate through the list of found updates and only those where the accumulated size is lower than specified.