Image Sizing | Configuring Subscribe2 HTML | Support | Semper Plugins

I have attempted to insert your solution, it has been edited to return array(250,250). However, I am still getting the issue that when the email is sent to Outlook the photo displays at full size. My WordPress version is up-to-date at 4.8.1.

Below is the latest  template I have tried. ( I tried using tables, but that only made things worse)

<div style=”font-family: Arial, sans-serif; max-width: 600px; width: 100%;”> Greetings,<br />

A new Nature Explore blog post is now available. Read an excerpt below and stay connected to all of the great work happening in Nature Explore Outdoor Classrooms across the country.
<div id=”email-img” style=”float:left;width:250px;padding: 15px;”>{IMAGE}</div>

<h4 style=”margin:0;padding:0;”>{TITLE}</h4>

{POST}

Thank you for being a part of this growing community!<br />

Sincerely,<br />

The Nature Explore Program
<p style=”text-align: center; font-size: 10pt;”>

You received this e-mail because you asked to be notified when new updates are posted.<br />

Please click the following link if you wish to unsubscribe: {UNSUBLINK}</p>

</div>

`<img src=”cid:53d3f29729e0985b55c377cf1f747fb1″ class=”attachment-250×250 size-250×250 wp-post-image” alt=”” srcset=”cid:53d3f29729e0985b55c377cf1f747fb1

1200w,

https://natureexplore.org/wp-content/uploads/2017/08/524_062-300×200.jpg 300w,

https://natureexplore.org/wp-content/uploads/2017/08/524_062-768×512.jpg 768w,

https://natureexplore.org/wp-content/uploads/2017/08/524_062-1024×683.jpg

1024w,

https://natureexplore.org/wp-content/uploads/2017/08/524_062-150×100.jpg 150w,

https://natureexplore.org/wp-content/uploads/2017/08/524_062-200×133.jpg 200w” sizes=”(max-width: 250px) 100vw, 250px”>`

After further review of the source code, I am going to guess that my issue lies with an image optimization plugin I am using called WP Smush. I still am looking into this.