Have set outlook for Calibre and 24 font and size.

This usually means the Zoom level for composing or reading mail changed, not the actual font setting. That matches the symptom where the message sends at the expected size, but looks tiny while typing.

For Classic Outlook for Windows, check these areas:

1. Open an email message in the Reading Pane.
2. Look at the bottom-right corner for the Zoom slider and increase it.
3. Click the percentage next to the slider to open the Zoom window.
4. Set the zoom to 100% or a larger value that is comfortable.
5. If available, select Remember my preference so it applies to all messages, then click OK.

If the issue is with the default compose font itself, verify it here:

1. Go to File > Options > Mail.
2. Under Compose messages, select Stationery and Fonts.
3. Under New mail messages, select Font.
4. Confirm the font, style, and size.
5. Repeat under Replying or forwarding messages if needed.

If custom font settings need to be reset to Outlook defaults in Classic Outlook, use:

• Font: +Body
• Font style: Regular
• Size: 11
• Font color: Automatic

Also, if the text only looks tiny while composing but sends normally, the accepted resolution in a similar case was that the Zoom setting had been changed to less than 100%.

• Change the default font or text color for email messages in Outlook
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