Yes, you can try encryption. .gov and .mil domain names may have additional security requirements or restrictions that may cause your email to be blocked or delayed. Blocked by a spam filter or the email was flagged as suspicious due to the content or attachments in the email.
It is recommended that you contact the IT departments of these organizations. They may be able to provide you with more information about their email policy and any specific requirements for incoming email.
thank you for your time and patience throughout this issue.
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