How to finally prevent Outlook 365 from resampling and re-compressing inline images, for good?

Question

There is this official Microsoft instruction: Turn off picture compression in [...] Outlook for Microsoft 365 saying:

Turn off compression in Outlook

The option to turn off picture compression in Outlook is available only after you have added a picture to an email message as an attachment.

1.      In the email message to which you have attached a picture, click File > Info.

2.      Under Image Attachments at the top, select Do not resize images.

This does not work and never has, at least not for (large) inline images. Such images are still resampled AND recompressed.

Then there is this advice on these forums:

1. If you copy/paste a .png image that has 32 bit depth, there will be no issues. As people reply to the e-mail, the image will remain as .png and the quality will not deteriorate in any way

This ALSO does not work, at least not for large inline images. Any image larger than 1672 pixels in any direction will be resampled to become 1672px wide and/or high, thereby deteriorating the image quality.

How can this finally be resolved?

It is unbelievable that millions of business Outlook users have had to put up with that embarrassingly bad and unprofessional quality of screenshots and similar images in emails, for decades.

Answer 1

Image size and quality option is not available in outlook 365... Where can I find this option? Please anyone help me.

When I flow the html file in outlook the image get compressed, please give the solution.

Answer 2

I'm not finding  do not compress images in file option in File >Options > Mail > Editor Options >Advanced in Outlook 365.

Could you please help out?

Answer 3

Dear Sir,

I am running Office 365 at work, and there is not any "image size and quality" option available under "File >Options > Mail > Editor Options >Advanced".

Is there another option to turn image compression off, such as by employing a registry entry? I am also very annoyed by the fact that Outlook compresses pasted images (also screenshots which have never been saved in any file format yet).

Thank you for your advice.

![](https://learn-attachment.microsoft.com/api/attachments/03435404-ce6f-473e-8df9-3716501e3ede?platform=QnA

Answer 4

Thank you Momo,

yes, I usually set this to "High Fidelity" and "Do not compress images".

However, this setting keeps getting re-set, and also it doesn't seem to keep Outlook reliably from recompressing images.

Answer 5

OK HERE IS HOW IT GOES

The images simply need to be in PNG format at 96dpi. Lossless DPI adjustments can be done quite easily for example with the free FastStone ImageViewer. Then, these 96dpi PNG images can be as large as you want, and their size, compression and quality will be 100% preserved when sending your e-Mail.

Contrary to what is written in many places, the images also do not have to be provided in 32bit color depth. This works just as well with 24bit or 8bit color depth.

These images keep their original resolution and quality even when forwarding or replying, both from Outlook.exe or from Outlook.com on the web!

Enjoy -- you can thank me later.