Synopsis
The name of a variable, or a label, was expected.
Cause
An add-on library, Exit handler, or Environment expected to be passed the name of a variable by your script.
Cure
Consult the documentation for that product to see what arguments you should be passing to a particular function/command that you're trying to use in that add-on library, Exit handler, or Environment. Look up this error message in that documentation. Check that you have the latest version of the software.
Cause
You put a colon (outside of any quotes), but there is no label name in front of it.
Cure
You must put a label name in front of an unquoted colon. Otherwise, if you don't intend to use the colon to denote a label, you must enclose the colon in quotes.