If you used the 'Prt Scr' button on keyboard to get a screendump image of the desktop, this can be 'Ctrl+V' (pasted) into a new Write message in the composing area. However, this would end up being very large and is not really the best method. So instead open up a paint program. Startup menu > type 'mspaint' and Paint window will pop up. Paste the image into Paint, perform any editing as required and then save as jpeg in a suitable location. Then in Thunderbird Write message * select the compose area * Using the 'Formatting Bar' select the 'Insert' icon and select 'Image * or toolbar - 'Insert' > 'Image'. * click on 'choose file' * locate file and click on 'Open' * click on 'Dimensions' tab * Select 'Custom size' and 'Constrain' then choose to reduce the size by: eg: * reducing a width from 2000pixels to perhaps 200pixels or * by reducing the percentage from 100% to maybe 10% Click on OK to insert the image.