Cause . . . . . : Signature '&8' was specified on the Start Program Export List (STRPGMEXP) command with one or more characters that do not belong to the invariant character set. This error occurred while compiling line &4 of binder language source &3 in file &1 in library &2 while attempting to create service program &5 in library &6. Recovery . . . : Change the contents of the explicitly specified signature to include only invariant characters and try the Create Service Program (CRTSRVPGM) or Update Service Program (UPDSRVPGM) command again. Technical description . . . . . . . . : If a signature is specified on the STRPGMEXP command, it must use only invariant characters.