Outlook Express message appears blank and has an ATT000XX.txt or an ATT000XX.htm attachment
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When you view messages in Outlook Express 5.x, the body of the message may be blank and the message may contain an attachment named ATT000XX.txt or ATT000XX.htm. If you use Outlook Express 6.0, the body of the message is blank and there is no attachment.
To resolve this behavior, clear the Temp and Temporary Internet folders:
In Internet Explorer, on the Tools menu, click Internet Options.
On the General tab, click Delete Files, click OK, and then click OK again.
In Windows Explorer, click to expand the hard disk letter, click to expand Windows, and then click to expand Temp.
Select all of the files, and then on the File menu, click Delete.