[SalesForce] Can you embed (not link) an image in an email template

I solved this with a simple VisualForce page by changing the ContentType attribute of the <apex:page> and by setting the Content-Disposition via a custom controller with ApexPages.currentPage().getHeaders().put('content-disposition','inline; filename=calendarEvent.ics'); in the constructor

<apex:page ContentType="text/Calendar" controller="CalendarInviteController">
    BEGIN:VCALENDAR
    VERSION:2.0
    PRODID:-//hacksw/handcal//NONSGML v1.0//EN
    BEGIN:VEVENT
    UID:uid1@example.com
    DTSTAMP:20170426T203000
    ORGANIZER;CN=ABC CO:MAILTO:education@ABCCo.com
    DTSTART:{!startDate}
    DTEND:{!endDate}
    SUMMARY:{!summary}
    STATUS:CONFIRMED
    LOCATION: {!location}
    END:VEVENT
    END:VCALENDAR
</apex:page>

public class CalendarInviteController {

    public String getLocation() {
        return location;
    }


    public String getSummary() {
        return summary;
    }


    public String getEndDate() {
        return endDate;
    }
    public String getStartDate() {
        return startDate;
    }

    private final String startDate;
    private final String endDate;
    private final String summary;
    private final String location;

    public CalendarInviteController(){
        ApexPages.currentPage().getHeaders().put('content-disposition','inline; filename=calendarEvent.ics');

        startDate = ApexPages.currentPage().getParameters().get('startDate');
        endDate = ApexPages.currentPage().getParameters().get('endDate');
        summary = ApexPages.currentPage().getParameters().get('summary');
        location = ApexPages.currentPage().getParameters().get('location');
    }
}

If all you see in your email client is "QR Code" (the image's alt attribute) it sounds like the email client is configured to not download images from external websites. Check if you have a warning similar to this:

(Image copied from https://www.wintips.org/wp-content/uploads/2017/06/image-8.png)

Alternatively you can also try to inspect the raw HTML of the message (in Gmail web client it's "show original" option in the dropdown menu) to verify the link is constructed OK, it's "just" that protection kicks in.

Not sure what you can do about it to be honest. Quite a lot of spammers / scammers / semi-legitimate marketing people try to get their images to display so they can "phone home" and report that this particular email was opened. It's called "tracking pixel" or "web beacon" and even SF uses it to track the Campaign Members.

Couple ideas:

• You could ask clients to add your emails to "white list" (this might mean adding Salesforce and / or this server that generates images for you)
• You could try embedding the image in the email directly. If you have the bitmap or PNG, you could save it as an Attachment under "this" record and then also add it as an Attachment to the email. It might be that the best way to do it will be to base64-encode the PNG and send it as "data URI scheme":
  • https://stackoverflow.com/questions/6706891/embedding-image-in-html-email
  • https://en.wikipedia.org/wiki/Data_URI_scheme (search for "red dot")
• You could add the document you need as a PDF attachment to your email (possible if you have a Visualforce email template). Normally the PDF generator SF uses doesn't display images from external servers nicely (that's why it's best idea to have them added to Static Resources or Documents). But if you'll add an exception to Remote Site Settings then the PDF generator should be able to fetch the image from external site and embed it nicely in the PDF)

• As for your #3, the Campaign Member Id missing - either you screwed up while anonymising the code to post it here or you're using the wrong merge field. You want it to be

  img src="http://api.qrserver.com/v1/create-qr-code/?size=200x200&qzone=1&data=http%3A%2F%2Fvictorng-dev-ed--c.ap2.visual.force.com%2Fapex%2FCampaignMemberQRCodeAttendance_Std%3Fid%3D" + {!CampaignMember.Id}
  

  right? not the QRCode__c. Again - your best choice would be to inspect the raw generated HTML of the email and experiment a bit. (And maybe use some URLFOR / URLENCODE to do the escaping automatically)