title: Can I send email with mailgun sandbox domain under my local OS?
body: <p>I registered myself at mailgun with domain I use for my laravel apps</p>
  <p>Also I see that with my domain there is sandbox domain, which looks like :</p>
  <pre><code>sandboxdXXXXXXXXXXXXXXXXXXXX.mailgun.org
  </code></pre>
  <p>and under SMTP block I see text:
  Grab your SMTP credentials:</p>
  <pre><code>SMTP hostname: smtp.mailgun.org
  Port: 587 (recommended)
  Username: postmaster@sandboxdXXXXXXXXXXXXXXXXXXXX.mailgun.org
  Default password: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX-XXXXXXXXXXXXXXXX
  </code></pre>
  <p>Working on my local OS, apache 2 under ubuntu 18
  I try to send email in my local having in .env :</p>
  <pre><code>MAIL_DRIVER=mailgun
  MAIL_HOST=smtp.mailgun.org
  MAIL_PORT=587
  MAIL_USERNAME=postmaster@sandboxdXXXXXXXXXXXXXXXXXXXX.mailgun.org
  MAIL_PASSWORD=XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX-XXXXXXXXXXXXXXXX
  MAIL_ENCRYPTION=tls
  MAIL_FROM_ADDRESS='from_email@site.com'
  MAIL_FROM_NAME='FROM NAME'
  MAILGUN_SECRET='XXXXXX-XXXXXXX'
  MAILGUN_DOMAIN='sandboxdXXXXXXXXXXXXXXXXXXXX.mailgun.org'
  </code></pre>
  <p>As result I sent email without errors, But I did not receive emails for 2 my users which are in Authorized Recipients of mailgun.</p>
  <p>What for this sandbox domain, can I use it for local OS and can I send emails under my local OS ?</p>
  <p><strong>UPDATED :</strong>
  In my local .env I set mailtrap.io params and it works ok.</p>
  <p>In Account Security-&gt;API security-&gt;API keys of my mailgun account I have parameters L</p>
  <pre><code>Private API key 
  Public validation key 
  HTTP webhook signing key
  </code></pre>
  <p>Setting app on remote dev server</p>
  <pre><code>MAIL_MAILER=smtp
  MAIL_DRIVER=mailgun
  MAIL_HOST=smtp.mailgun.org
  MAIL_PORT=587
  MAIL_USERNAME=XXX
  MAIL_PASSWORD=XXX
  MAIL_ENCRYPTION=tls
  MAIL_FROM_ADDRESS='from_email@site.com'
  MAIL_FROM_NAME='FROM NAME'
  </code></pre>
  <p>If MAIL_USERNAME and MAIL_PASSWORD must be filled with values from Account Security-&gt;API security-&gt;API keys
  also if MAIL_FROM_ADDRESS must one of Authorized Recipients I created in the settings before ?</p>
  <p><strong>UPDATED BLOCK 2:</strong>
  I try to fill parameters from live domain, but failed.
  I search paramters here : <a href="https://prnt.sc/18ouojv" rel="nofollow noreferrer">https://prnt.sc/18ouojv</a>
  ?</p>
  <p>Thanks in advance!</p>