Report Offensive Message

Easily if the compression you use consolidate multiple files into a single file (such as using WinRar to create a .rar file). As for NTFS native compression, it will use the allocation unit size as the smallest unit. The size on disk will not decrease unless you compress multiple files into a single file or compress files from a multitude of units to a smaller number of units (ie large file compression.) It is never a good idea to compress a folder using NTFS compression if it is exclusively 1-2 unit size files. You will just be wasting resources and not getting any smaller data.