ISA Server implements a cache of frequently requested objects to improve network performance. You can configure the cache to ensure that it contains the most frequently used data.

By default, when you install ISA Server, caching is disabled. This is because no space on any disk drive on the ISA Server computer has been specified to be used for caching. When you configure a drive for caching, by specifying how much space to use on the drive, you enable caching. You can further configure the cache, specifying which content can be cached.

For instruction on how to enable caching, see the product documentation.