<div dir="ltr">We are also seeing this. Support let us know there were some issues with emails from the Barracuda cloud, but we are on-prem.<div><br></div><div>451 4.7.500 Server busy. Please try again later from [103.21.17.178]. (S77714) [<a href="http://ME3AUS01FT022.eop-AUS01.prod.protection.outlook.com">ME3AUS01FT022.eop-AUS01.prod.protection.outlook.com</a> 2023-10-11T04:06:47.950Z<br></div><div><br></div><div>The queue is over 4000 emails at the moment. </div><div><br></div><div>- Max</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, 11 Oct 2023 at 15:24, Shane Chrisp <<a href="mailto:shane@2000cn.com.au">shane@2000cn.com.au</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><u></u>

  

    
  
  <div>
    <p>Hi All,</p>
    <p>Just wondering if others are seeing issues with email for
      delivery to Outlook 365 queuing up with "<span style="color:rgb(38,38,38);font-family:Lato,Helvetica,Arial,sans-serif;font-size:15px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb(245,245,245);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">4.7.500
        Server busy. Please try again later" messages? <br>
      </span></p>
    <p><span style="color:rgb(38,38,38);font-family:Lato,Helvetica,Arial,sans-serif;font-size:15px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;word-spacing:0px;white-space:normal;background-color:rgb(245,245,245);text-decoration-style:initial;text-decoration-color:initial;float:none;display:inline">Our
        mail queue has been getting progressively larger since about
        10am WAST today and of course the MS outage site shows no
        issues, though some of the down detector sites how others seem
        to be having issues.<br>
      </span></p>
    <pre cols="72">-- 
Regards

Shane Chrisp
2000 Computers & Networks Pty Ltd
U8, 19 Outram St, West Perth, WA 6005
Ph 08 6298 7391 Fx 08 6298 7393
Mb 0412 409 856
Email <a href="mailto:shane@2000cn.com.au" target="_blank">shane@2000cn.com.au</a>
Web <a href="http://www.2000cn.com.au" target="_blank">http://www.2000cn.com.au</a>
</pre>
  </div>

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