Just a quick note about Windows Vista (and probably Win2008 and Win7).
WatchDirectory's File Age monitoring method can detect "old files" based on their "Last Access Time" (the last time the file is opened). This timestamp is maintained on NTFS volumes when the registry key
is set to zero or does not exist.
Windows versions before Vista defaulted this setting to zero, so the Last Access timestamp was maintained for files on NTFS volumes. To improve file system performance, Microsoft disabled Last Access recording on Vista.
If you want to detect "old files" based on their Last Access time, please make sure this registry setting is set to zero.