eM Client 10 Beta 2 asks senders account Login and Password

This is the first time I’ve come across something like this.
To open the sender’s email I am asked to enter their account details. Not mine, theirs.
If I click Cancel, the email can still be read, but it looks very strange.

Does it happen on every mail?
Can it be that the mail is encrypted?

Yes agree with @PoulBak does sounds like a possible password protected email where the sender sometimes eg: SMS’s you the login and password separately to open or view the email.l when received.

So if you know the sender then suggest to contact them by Phone or SMS and ask them have they enabled something in that sent email which requires a login and password.

If they haven’t or you don’t know the sender, it might then be a phishing type email trying to get your login details in which case you can block that in eM Client via the move to junk and blacklist email address.

Now if it’s happening to every email you get sent by this sender and not any other emails, then ask the sender what mail client they are using as might be a problem with their mail client they are using.

Only with this email. No, is not encrypted and i can open this email in Outlook as normal, no passwords needed. And if i close the password window, the email can be read that way.