If you're using Internet Explorer 6/Outlook Express 6, you might check this.
Open Outlook Express, click on "Tools" in the upper left, choose "Options", then click on the "Security" tab, UNCHECK the box that says: "Don't allow attachments that could be viruses to be saved or opened". Click on "Apply", the OK, etc.
If that doesn't fix the issue, then please tell us the file extensions of the attachments which aren't opening. (The three letters after the dot in the file name, like .txt or .doc.) You may need to install the program which is associated to those file extensions.
Hope this helps.
I have outlook express on my Dell Demension 4700c and for some reason it has decided not to let me open any attachments on my e-mails. have tried closing spam blockers and nothing has worked. even called my provider and that didnt help . Any sugestion would be greatly appreciated