Is there an Infobar displayed above the message which tells you that Outlook
has converted the messages for you?
If so, toggling the option to read all messages in Plain Text (Tools-> Trust
Center-> E-mail Security) will only have an effect on newly received
messages.
If that option isn't selected and you still receive all messages in Plain
Text it could be that you have something installed that does the conversion.
Anti-malware suites also often have this option. Message corruption is also
a known source and are often caused by these very same anti-malware suites.
(Older versions of?) AVG has a reputation of causing this as they modify the
message body with a "Scanned by" line. Disable the virus scanner's
integration with Outlook and try again.
See
http://www.msoutlook.info/question/20
--
Robert Sparnaaij [MVP-Outlook]
Coauthor, Configuring Microsoft Outlook 2003
http://www.howto-outlook.com/
Outlook FAQ, HowTo, Downloads, Add-Ins and more
http://www.msoutlook.info/
Real World Questions, Real World Answers
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"adrian prior" <(E-Mail Removed)> wrote in message
news:C2A85443-362B-4289-839D-(E-Mail Removed)...
> I am running Windows XP Pro with Microsoft Office 2007. When opening
> outlook,
> all my emails are displayed in plain text. I have tried changing the
> security
> setttings to display messages in HTML but this had no effect. Can anyone
> help?