This is really weird... When I open the following simple HTML document in Internet Explorer 7.0.5730.11 (on Windows Server 2003 Web Edition SP2)
<html>
<body>
<p>+</p>
</body>
</html>
it shows me a totally blank page. FWIW, this is just a trivial "repro" sample. In real HTML documents, I observed other, even more bizzarre effects caused by presense of the "plus" character that follows a tag.
NB: The problem appears to be extremely ittermittent. Most of the time it does work properly (i.e. displays the "plus" character), and I still can't find any way to reproduce this problem at will.
Some additional details based on recent comments:
There was no server involved. I was opening a file on disk (i.e. used file:// protocol).
The file did not contain anything except five lines shown above. No document type declarations, no character encodings, no nothings.
Looks like a bug in IE. Did anybody encounter the same or similar problem?
NB: I appreciate all the responses received so far, but neither of respondednts encountered this problem. Something tells me that 99.(9)% of StackOverflow audience will not be able to reproduce it. :-)