When checking the existence before the drop remove the use acces and the go statements between begin and end.
Create procedure should be the first statement in a query batch therefore the existence can’t be checked.
I also have a problem with the square brackets, if the name of the procedure is 29 or 30 characters long, which is the maximum allowed in my configuration, the server (ASE 12.5.3) tells me that the name is too long. With ASE 15.5 there is no problem.
Why is there a [dbo]. on the drop procedure statement. I am not using fully qualified object names.