Occasional text formatting issue in emails received by recipients

[Terrible Toll]

I have a curious problem that occurs occasionally with HTML emails sent through our CloudMail system.

The emails are all sent out correctly formatted. I copy all emails to a server inBox  so that I can log what was sent out and see exactly what was sent. Some recipients are receiving emails, but seeing them formatted to a 100px width, making them very hard to read. I have examined the email header and it contains a line that I cannot fathom how it got there:

style=3D"margin: 5px; width: 100px; height: 100px; font-style: normal; = ...

I am investigating this further - my trouble is that I cannot repeat the problem and I have yet to discover a pattern. If I remove the styling in the email, the problem is removed (but so is the styling and any hyperlinks).

It does not appear to be anything about the recipients chosen email system, but it may have to do with a reencoding of the header by a corporate server or Spam filter.

More soon,

Anatole

[Terrible Toll]

The emails are somehow being re-encoded for this 3D style. It was not created this way. Whether this is by the AWS SES system or when it is received by my email app, I don't know. Could it be that certain browser versions (prob Outlook for Windows) are misinterpreting the width and applying it to the whole message?

I have removed any reference to 100px width margins from the HTML message template in the hope that this might fix it!