Hi,
please try ./SYBASE.sh
There are no spaces and don't forget the slash /
If this does not work, please type on the shell: id
This will print the current user. So we can see whether you're really logged on as sybmk1.
If you receive any other errors, please execute: echo $SHELL
This helps us to identify whether you're using the right file for your shell.
Best regards,
Juergen