We have a bunch of external users from a partner company who, up until a fortnight ago, were able to access an few apps containing reports. It's slightly outside my sphere of knowledge about what needed to be done, but it was working.
Now, however, they're all getting a 'We don't recognise you. Are your credentials correct?' error message with a picture of an owl (or, as my colleague suggested, a fat penguin). It's only people accessing externally (i.e. outside our tenant).
As far as I'm concerned, as the person responsible for the Power BI platform, nothing on our end has changed. Has Microsoft snuck through an update that I've been utterly unaware of? If they have, what do I need to do to reinstate peoples' access?