How do you intend to use Open URL?
Please note that Open URL will work fine from a database hosted by server as long as you use it on a client computer. This is only an issue if you use server to schedule a script with this step or if you use the new perform script on Server script step--neither of which would seem to make sense to use with Open URL as the File or web page thus opened would not be visible to your client machines anyway.
Thanks for reply. I want to execute php file on server annd this script will be scheduled script
You may need to use an OS based task scheduler that uses a FileMaker "Robot" file to do this. That will work from a "client" context and thus avoids this limitation.