Your license information includes a licensed to name which must be entered either in the name or orgnazation field, EXACTLY as it is written for the key to work.
You can copy/paste that as well to make sure you are copying it correctly.
As instructed by the message from FileMaker, I to to My Profile on this site, where I find a Lincense Key, but there is no "licensed to name".
Then I would suggest that you look at your profile and enter the first and last name in your profile as it is entered.
Tom may have too much going on,
Have you turned off Virus protection?
Quit all open applications?
What OS (Mac or Windows) version are you installing on?
Does the hardware meet the minimum requirements?
If you call FMI technical support they can validate your License Key. I think if you ask they will make it a no-charge support call.
The developer license keys are not keyed to any name or organization so you can enter any name and it will install.
Organization is not required unless Name is blank.
That was it: I needed the first and last name in my profile, on a different tab.