Hello. I am having the similar kind of problem with MS Outlook-2007 ( Windows7, 64bit). While I clik or double click on the attachment, specially a PDF file, it hangs for few seconds and then performs the action. There is no problem with other fomat attachments like word, excel or picture files.Even if I want to attach a PDF file to new mail then also it hangs. If any body have any solution then please help me.