Why are the images from the FYI Email Signature enlarged when viewing in the desktop version of Outlook?

Issue

When using the desktop version of Outlook, images in the email signature appear much larger compared to images displayed in FYI or when using the web version of Outlook.

Cause

The desktop version of Outlook may ignore the height and width dimensions set within the email signature and instead display the image at its original pixel dimensions.

If the original image file is large, Outlook will display the full-sized version of the image.

Solution

Resize the image used in your signature Email Templates, ensuring the email message (including the signature) does not exceed the message size limitations. For guidance on editing signatures, refer to Creating Email Templates and Signatures. For details on file restrictions managed in FYI, refer to File Limits.

When updating the signature image:

1. Resize the logo using image editing software before inserting or re-uploading it into the template in FYI.
2. Create a test email in FYI to confirm how the signature displays in the desktop version of Outlook.

As a best practice, keep signature images to a maximum of 300px - 600px wide, depending on the logo proportions, and under 100KB in file size. Use an optimised PNG for logos with transparency, or a compressed JPG where transparency is not required. Resizing images can be completed using standard image editing software, for example, Photos in Windows 11.

Note: The way the image is displayed is determined by the desktop version of Outlook and is not managed by FYI.