The recipient is outside your tenant

Hi,

We're not sure why we are getting this. 

When sharing a dashboard I type the users who should have access within our organisation and add them.

We have our active directory domain which is @example.ac.uk but our email addresses are @something.ac.uk

For the majority of our users, when you click on the 'Access' tab they have been added fine using the domain. But a small number when using the domain show as 'Guest' with 'The recipient is outside your tenant. Their access is limited and the dashboard will be read only.'

So for some users whether you trying adding using the domain or email address it gives the message above.

Does anyone know why this is happening? All users in our organisation have the same setup of the AD domain and the email address.

Any guidance appreciated.

Thanks