AnswerThis folder is used to store the downloaded web content that is scanned and cached by WebMonitor. By default the downloaded files are cached for 27 hours.
This can not currently be changed in WebMonitor 2015 and newer versions.
The change the retention of the cached files in GFI WebMonitor 2013 and previous versions:
Open the GFI WebMonitor Console go to Settings > General > Options, and modify the Downloaded files cached for value.