Can't access closed beta

@ica-ab you need xbox live to play bud

have him create a microsoft account by making an email at outlook , hisemalename@outlook , this will be his microsoft password when he makes that email. now he can join xbox live and use the insider hub for xbox live, all free on the PC, no xbox needed. on windows 10 , witch he must have, click bottom left corner start menu, the o icon, then look for or search for xbox insider hub app. sign up and download it free. once he has done that. Now here is the topic copy and pasted from instructions here on forums .

Xbox Insider Hub for PC - Installation & Troubleshooting
By RareCSM
Last Updated: January 26, 2018
Here you will find all the information required to install the 'Sea of Thieves Closed Beta' via the insider hub.

Here's a few things to check before getting started:

You are signed into Windows 10, the Store and the Insider Hub with the correct account. Access to the Technical Alpha is linked to your Gamertag, so you must be signed in with the associated email address and password that you used when you signed up for the Sea of Thieves Insider Program.
Windows 10 Anniversary is installed and up to date (very important)
Now that you've checked all of the above, let's get going.

There are three stages from start to finish: Install the Insider Hub, find Sea of Thieves in the Hub and finally install the game from the Hub and Store. Follow the steps below:

Press the Start key and open the Store
Search for and install the Xbox Insider Hub
Launch the Hub and you'll find Sea of Thieves waiting for you listed under "Insider content"
Click the icon which will take you through to the Store page
Click install and the download will begin. The download is around 8GB.
If the game does not appear in the Insider Hub, check the prerequisites above. If the game is still not showing, or is failing to install, try these steps:

Launch the Xbox Insider Hub.
Navigate to Insider content > Sea of Thieves.
Select Manage.
Select Unenroll.
Return to the Sea of Thieves page in the Xbox Insider Hub, and select Join.
Try the installation again.
If you are still experiencing issues, please follow the steps Here to create a new local administrator account. Once created, sign into the Store and the Insider Hub with your Gamertag and try the installation again.

If these steps do not work, raise a ticket with our Customer Services Team

Yes he has tried almost everything that we could come up with and he has followed every instruction on how to fix the problem.
However the main issue is that A. The Closed beta App in the store is locked for him even though he bought the game directly from the store. It simply says "not available".
And B. He can't access the forums because he keeps being told to make an xbox live account which he already has made, or the Insider hub since he keeps recieving access errors. (this is also the reason i'm posting this and he hasn't opened a support ticket.)

Update: It appears that he managed to resolve the issue by cancelling his pre-order and purchasing it for a completely new account which had access to the Insider hub.