Blank body of email /

Some messages I open in Outlook 2007 look blank but are of a very faint
yellow font in the body of the message. I can do a ctrl A and copy the
message into an editor and then read it. Also, sometimes when I reply or
compose a new message, I cannot type any text. It appears as if the text I am
typing is of a white font so I then have to go and select Automatic to change
it to black. This does not happen with every email I compose or reply to or
open as there doesn't seem to be any consistency to it. I have removed and
reinstalled Office 2007 to no avail, and am also not running AVG antivirus.
Everything works normally when I start Outlook in Safe Mode. Any ideas?

thanks