HTML E-mails are Blank

I recently moved a licensed EE 2.5.2 site to a new server and now when I send HTML e-mails using the communicate tool the e-mail is received but the message body is blank. The subject is intact as well but nothing at all in the body of the e-mail. I can successfully send plain text e-mails using the communicate tool without any problems. I suspect this could be related to the server configuration since nothing else has changed. Any tips or advice on resolving this issue would be greatly appreciated, thanks!