First who is sending you these pictures with the extra added attachments?
Second they might be infected with some type of email bug that sends out these extra attached pictures to other people and I would ask them if they are actually sending these pictures to you? They may be totally un-aware they are doing this. If they tell you that they are not doing this then ask them if they frequent the XXX sites? If they say no they do not then ask them where they get the pictures they send you. This is sort of like you are going to be Dick Tracy master detective.
I also would like you to submit a HijackThis log file to see if your system has gotten an infection.
To download HJTsetup.exe To Download HijackThis go to the following: http://www.thespykiller.co.uk/forum/index.php?action=tpmod;dl=item5
Filename = 1137518044HJTsetup.exe
Save the file to your desktop.
Double click on the HJTsetup.exe icon on your desktop.
By default it will install to C:\Program Files\HijackThis.
Continue to click Next in the setup dialog boxes until you get to the Select Additional Tasks dialog.
Put a check by Create a desktop icon then click Next again.
Continue to follow the rest of the prompts from there.
At the final dialog box click Finish and it will launch Hijack This.
Click on the Do a system scan and save a log file button. It will scan and then ask you to save the log.
Click Save to save the log file and then the log will open in notepad.
At the top of the Notepad HJT log screen, hit Edit then Select All then click Edit and then click Copy doing that copies the text to the clipboard, you won't see it yet....
Come back here to this thread and Paste the log in your next reply. DO NOT have Hijack This fix anything yet. Most of what it finds will be harmless or even required.
A security expert should take a look at your log - please be patient.