The FairCom Server configuration option FILESYS_COMPRESS_FILE can be used to enable file system compression on files whose names match the specified filename, which can include wildcard characters. The compression is enabled at the time that the file is created. This option only affects data and index files, not transaction logs or CTSTATUS.FCS.
Limitations
Currently, support for file system level compression is implemented only on Windows systems, using the built-in compression feature of the NTFS file system.
https://docs.microsoft.com/en-us/windows/win32/fileio/file-compression-and-decompression
Example
FILESYS_COMPRESS_FILE custmast.dat
FILESYS_COMPRESS_FILE custordr.dat
FILESYS_COMPRESS_FILE ordritem.dat
FILESYS_COMPRESS_FILE itemmast.dat