You can either use a photo application on your computer, or if you dont have one, you can use a web site to resize the photo. a quick search found (You need to Login or Register to view media files and links) which seems pretty easy to use.

As for the HTTPS part, as long as you just attach the photo to the message, like you did above, you dont have to worry about it. The HTTPS is if you have a picture on another web page somewhere, that you want to show off in the forum using the "insert image" button. In that case you have to use an HTTPS link to that other web page for it to show up properly. An example would be if you used Photobucket.com, you would have to use (You need to Login or Register to view media files and links) instead of (You need to Login or Register to view media files and links)

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