The file popmail.exe.Z is the popmail program, compressed with the UNIX "compress" utility. It is intended to be uncompressed on your UNIX machine. To uncompress it, type "uncompress popmail.exe.Z" at the UNIX command prompt. The file popmail.exe is the popmail program without any compression at all. The file popmail.exe.uu is the popmail.exe file encoded into ascii text with the Unix uuencode command. You will have to use uudecode to reconstitute this file. Be sure to put the ftp session in binary mode when you transfer the popmail program files. Please send bug reports to: popmail@boombox.micro.umn.edu