Running Microsoft Fortran, long discontinued. Running under WinXP Pro, SP2, Command Prompt subset. Ran this program previously under Dos, very large, subroutines overlayed several times. Two things now happen, getting error “out of memory”. I ran the program under an emulator called “DosBox” runs ok but now having problems with the calls to DSRT, DSIN, DCOS, “Domain” errors. Seems like the functions are being corrupted after the first call, etc. Could be a problem with the Dos emulator “DosBox” running under WinXP or? Mystified. How can i get more memory under the Dos subset in Win XP or “DosBox” or??? Anybody have any ideas? Sid Kraft, sid_kraft@msn.com.