Hotmail mailboxes receive mail as MIME

[Juliop]

I upgraded my Mac to 8.4.9 and now the recipients of emails hotmail present the message:
"This message is in MIME format. Since your mail reader does not Understand this format, some or all of this message May not be legible."
For recipients of Yahoo and Gmail message reaches them perfect.

I appreciate your help.

 

[stanbusk]

We changed nothing to message formats actually, MaxBulk Mailer v8.4.9 is the same as v8.4.8
What format are you using, HTML?

 

[Juliop]

Thank you. I've found the problem. I eliminated a numerical header was added in preferences and messages flowed seamlessly into Hotmail.