Mozilla Thunderbird wont load my pictures

[Cdub89]

I just downloaded Mozilla Thunderbird i like it and everything but i have one concern. My friend sent me a email that has pictures, i open the email up and double click attachments and all the pictures do is appear as a red x. Do i have to download another little program or something? I remember outlook express did this to me but i would just click attachments again and they would appear. Anyone have any ideas? Thanks