"can't read control file" bootldr error

I tried to use bootldr 2.21.12 to read the jffs2 file on my 512mb SanDisk CF card (ipaq h3900). It says "can't read control file" every time i try to do the flash thing in bootldr. I have tried FAT16 and FAT32 and both give me the same error. I have also tried 2 of ther CF cards. I hear all this stuff about updating through command prompt, but i have nothing like a command prompt. I press the bottom 4 function buttons and none of them seem to do anything. They select the text in blue, but don't do anything. What is the problem?

thanks