I cannot paste an image in Microsoft Outlook 2000

Hi All,
I am using an HP machine running on Microsoft Windows XP. And, my Microsoft Outlook’s version is 2000. Previously, I am used to copying an image from the internet and once I am done, I will paste it on the body of the email in Outlook. It was working perfectly few months ago, and now that I need to send an image, it is not pasting it.
I have tried restarting the computer. Also, I tried copying the image from the net, then pasting it in a Microsoft Word document and it is working. I tried it again in Outlook, but no success.
Please help.
