| You can 'edit' one of your existing posts in this thread and at the bottom you will see a button with Browse on it. Click on that and browse to wherever you've put the photo on your PC and then click on ok. then click Edit and Roberts your mothers brother.
Or, you can get to the same place by clicking on Post Reply instead of using the Quick Reply feature. The Browse button will be at the bottom for this as well.
It says Attachment in the far left of the field. | 
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