A. Your error message may well be "unknown subscriber" or "network error". You probably have to enable picture messaging (MMS messaging) with your network. Visit your network's website, create an account with your phone number, find information on MMS messaging and follow the instructions. It's quite straightforward. Failing that, call your network provider. They send you a text message that will set your phone up. Find help pages for the six main suppliers using these links.

• 3
• T-Mobile
  (dial 150 from your t-mobile phone, then 1, and 3 for an operator)
• Orange
• 02
• Virgin
• Vodafone.

A. We run a network check on your phone. If you don't have enough credit, or your phone is brand new and has not made enough calls for us to verify it then we don't publish the ad, or charge you.

A. The text in the subject line won't appear on the site anyway. Put the text in first then select the image. You'll have loads of space to put your text in.

A. It's possible the content of your ad is too large for your network. Try editing your ad. The largest part is likely to be a movie, then a sound file, then an image, then your text. It's unlikely to be the text. Read "Advice for buyers & sellers" for guidance on making your ad.

A. Click here for information on charges from your network provider.

A. You can get up to a thousand characters (perhaps more, depending on your network) if you send an MMS message, but don't include an attachment. This may mean you will pay more for the message than a plain SMS message. Click here for more information about your providers charges. Look at our "Advice for buyers & sellers" page for a information on the difference between MMS and SMS messages.

Your Internet Explorer internet settings in "check for newer versions of stored pages" (tools/internet options/Browsing history/settings). need to be set to "everytime I visit the webpage", and not "automatic".