The first time you start NinjaTrader after importing the toolbox, a small window asks for your email address. Here is what it wants, and why.
What to type: the email address your NinjaTrader account is under. Type it exactly as it is registered — same capital letters, no extra spaces before or after it. A stray space is the most common reason an address comes back as not found.
Not accepted? If you subscribed under a different address before, type that one instead — for a few long-standing customers that is what I have on file.
What it is for: the toolbox saves the address and uses it to check your subscription when it looks for a new version. That is all it does with it.
Separately, the tools themselves are licensed to your NinjaTrader account. So NinjaTrader has to be running under the NinjaTrader account you subscribed with. If it is not, the tools will not load at all and NinjaTrader shows you a license message instead of this window — that one is a different problem, and it is covered here:
License not working or tools won't load
The window never appeared? Close NinjaTrader completely and reopen it — the window only comes up at startup. If it still does not appear, check that the import finished without errors in Control Center → Log. Then submit a request through the support form and I will take it from there.
Bernard