The URL to navigate the prompter panel to. Will be ignored if the prompter_wrname property is specified.
Blank – the prompter does not navigate to a URL.
A valid URL, in single quotes. Note that a protocol (for example, http: or https:) must be specified.
The URL must be from the same server that the WAM is from. Browser security restrictions prevent code in a page from one server accessing information in a page from another server. Using a URL that points to another server will cause the prompter code to fail with a "permission denied" error.