>From a network file server what windows calls need to be made to determine the OS of the server? The exe file is resident locally and I need to print using custom paper sizes on printers located on other machines or even the server. Thanks.

Calvin,
If the systems are NT derivatives then you can use ADSI to do this.

ocomputer = GETOBJECT('WinNT://MyComputer,computer')
? ocomputer.OperatingSystem   && returns something like Windows NT
? ocomputer.OperatingSystemVersion  && returns version (i.e. 4.0)

HTH.