Hostname returned invalid syntax for SPF record. We detected a problem with the syntax of your SPF record. Your record must adhere to specific guidelines from RFC 7208. If your record does not meet those guidelines then the syntax error could cause your record to be read incorrectly and block email that you do not intend for it to block. This can make it very difficult to know why messages are being blocked as SPF is often used as part of spam filtering which may not specify that it is an SPF Record Syntax issue that is causing the problem.