REBOL 3 Errors: locked-word

An attempt was made to modify a protected word. The word will have been protected with the protect function.

Message:

["Word" :arg1 "is protected, cannot modify"]

Example:

my-word: "data"
protect 'my-word
filter-error try [my-word: "new data"]
** Script Error: Word my-word is protected, cannot modify
** Where: my-word: "new data"