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Usually, the default 60 minutes of Maximum Run Time is enough for us to install CU.
And of cource, we can increase the limit to 120 minutes to get a better success install, but if we configured the maintenance window, Configuration Manager also uses this Maximum Run Time setting to determine whether to initiate the software update installation within a configured maintenance window. If the maximum run-time value is greater than the available remaining time in the maintenance window, the software updates installation is postponed until the start of the next maintenance window. So we need to make sure to set the maximum run time value smaller than the configured maintenance window time or increase the maintenance window time to a value greater than the maximum run time. Otherwise, the software update installation will never initiate.
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