Cheryl is having issues typing a comma in her web email. It changes to a symbol for some reason. Leo says it sounds like a typeface or font problem. It's probably damaged and can't find the comma, so it inserts something else. She should try changing the default fonts in her browser settings to another default font. Leo suspects that her ISP is sending a corrupted font. So she'll have to take it up with them.
She should also try a different browser. If that works, then her browser is corrupt. She can restore default settings, and this article at answers.microsoft.com will guide her. She should also try this from tenforums.com.